Knowledge, Practice, and Associated Factors of Nurses in Pre-Hospital Emergency Care at a Tertiary Care Teaching Hospital

Hailemichael Abate, Chilot Mekonnen

Open Access Emerg Med. 2020 Dec 31;12:459-469

Background: Pre-hospital emergency care is a medical care given to patients before arrival in the hospital after activation of the emergency team. Poor knowledge and practice about pre-hospital emergency care hurt the health outcomes of the patients.

Objective: This study aimed to assess knowledge and practice nurses at the University of Gondar Compressive Specialized Hospital, Northwest Ethiopia.

Methods: An institutional-based cross-sectional study was conducted from March 20 to April 10, 2020. A stratified sampling technique was used to select the study participants. Data were collected using a pretested structured self-administered questionnaire. Data were analyzed using SPSS version 20. To explain study variables, frequency tables and percentages were used. Logistic regression analysis was used to see the association between independent and dependent variables.

Results: Out of the total 378 respondents, less than half (42.9%) had good knowledge; similarly, 49.5% of them had good practice about pre-hospital emergency care. Male sex and attend formal training were significant associations with both knowledge and practice of pre-hospital emergency nursing care. Male participants (adjusted odds ratio (AOR) = 6.57, 95% confidence interval (CI) (3.79-11.36)) and having training (AOR=1.74, 95% CI (1.83-3.66)) were significantly associated with knowledge of pre-hospital emergency care, whereas male sex (AOR=1.73, 95% CI (1.09-2.73)) and having training (AOR=6.16, 95% CI (2.69-14.10)) were significantly associated with the practice of pre-hospital emergency care.

Conclusion: Knowledge and practice of nurses regarding pre-hospital emergency care was found to be inadequate as compared to previous studies. Male sex and attend formal training showed a positive and significant association with both knowledge and practice of pre-hospital emergency nursing care. The responsible body ought to allow professional development and attending formal training for nurses.

 

Comparison of the Effectiveness and Comfort Level of Two Commonly Used Mask Ventilation Techniques in a Model

Saqer M Althunayyan, Raied N Alotaibi, Mohammed A Aljanoubi, Musab Z Alharthi, Abdullah M Mubarak, Ahmed M Al-Otaibi

Respir Care. 2021 Mar;66(3):460-465 

Background: Mask ventilation is an important rescue airway skill for providing oxygenation and ventilation. Maintaining a good face mask seal is a fundamental factor for successful ventilation. Therefore, the aim of this study was to compare the effectiveness and comfortability of 2 commonly used mask ventilation techniques.

Methods: A randomized crossover study was performed to compare the 2-handed C-E and 2-handed V-E techniques on a simulation model. Respiratory therapists were recruited by convenience sampling to hold the mask during mechanical ventilation with a fixed tidal volume (VT) of 500 mL, a rate of 12 breaths/min and a PEEP of zero were provided. Each participant performed a 2-min ventilation session, with a total of 24 breaths for each technique. For each technique, we recorded the median VT and the number of successful breaths (≥300 mL). Provider comfort was assessed by using a 5-point Likert scale at the end of the 2 techniques. Subgroup analyses were conducted for sex, experience, and height of the participants.

Results: Of the 75 respiratory therapists recruited, 74 participants were included in the analysis. There was no statistically significant difference in the median VT between the V-E (417 mL [interquartile range, 396-427] mL) and C-E techniques (410 [interquartile range, 391-423] mL) (P = .82). Approximately 74% of breaths delivered by the C-E technique were effective, whereas only 68% of those delivered by the V-E technique were effective (P < .001). Most of the participants reported that using the 2-handed C-E technique was more comfortable.

Conclusions: In our study, the median VT did not differ significantly between the 2 techniques. However, the C-E technique seemed to be superior to the V-E technique in terms of the number of effectively delivered breaths and comfortability. Further studies are recommended for basic airway management techniques.

Morbidity And Mortality Among Patients Sustaining Chest Injury Due To Blunt Force - The Difference Between Young And Elderly

 Ambreen Abid, Tanveer Ahmad, Pratikshya Thapaliya, Surrendar Dawani, Nazish Sikander, Misauq Mazcuri

Ayub Med Coll Abbottabad  Oct-Dec 2020;32(4):512-516.

Background: Blunt Chest trauma (BCT) is caused by road traffic accidents (RTAs), falls, assaults, or occupational injuries. Age has been hypothesized to be a predictor of complications and adverse outcomes in the elderly. This study aimed to compare morbidity and mortality in young and elderly patients with BCT.

Methods: This prospective two-arm study was conducted in Jinnah Postgraduate Medical Center, Karachi from July 1st till 31st December 2019 after approval from the Institutional review board. All hemodynamically stable patients with BCT presenting in the emergency were stratified in two groups. Group A included patients age 12-45 years; Group B were of age ≥65 years. Their clinical characteristics, complications, and in-hospital outcomes were compared. Data was analysed using SPSS version 16.0.

Results: There were 39 (55.7%) patients in group A and 31 (44.3%) in group B. RTAs were a significant cause of BCT in Group A (p=0.01) and falls in Group B (p=0.003). Lacerations, open wound, and flail chest were significantly more common in Group A (p≤0.05). Complications of BCT including pneumonia and acute respiratory distress syndrome (ARDS) were significantly higher in Group B (p≤0.05). Group B required mechanical ventilation more often (45.2% vs. 12.8%; p=0.003). There were seven deaths in Group B (p=0.002) and none in Group A.

Conclusions: Commonest cause of BCT in the elderly is falling. Similarly, the elderly are more prone to develop pneumonia, ARDS, and the need for ventilatory support. Early intervention to control pain, improve ventilation, and chest physiotherapy reduce the risk of morbidity and mortality.

Early and Ultraearly Administration of Tranexamic Acid in Traumatic Brain Injury: Our 8-Year-Long Clinical Experience

Nurdan Acar, Mustafa Emin Canakci, Ugur Bilge

Emerg Med Int. 2020 Sep 18;2020:6593172

Introduction: The most important result of head trauma, which can develop with a blunt or penetrating mechanism, is traumatic brain injury. Tranexamic acid (TXA) can be used safely in multiple trauma. Recent studies showed that TXA can be useful in management of intracerebral hemorrhage, especially in reducing the amount of bleeding. The TXA given in the first 3 hours has been shown to reduce mortality. The aim of our study was to evaluate the effectiveness of tranexamic acid used in patients with traumatic brain injury.

Method: Patients with trauma in the emergency room between January 2012 and January 2020 were screened in this retrospective study. The inclusion criteria were being over the age of 18 years, tranexamic acid administration in the emergency department, and traumatic brain injury on brain computerized tomography (CT) and control CT imaging after 6 hours.

Results: The number of study patients was 51. The median score of GCS was 12.00 (8.00-15.00). Subdural hemorrhage and subarachnoid hemorrhage were the most common findings on brain CT scans. In the group TXA treatment for less than 1 hour, the arrival MAP was low and the pulse was high (p=0.022 and p=0.030, respectively). All the patients were admitted with multiple trauma. None of the 51 patients had thrombotic complications and died due to head injury.

Conclusion: TXA appears to be a safe drug with few side effects in the short term in head injuries. According to our experience, it comes to mind earlier in multiple trauma, especially in head trauma with pelvic trauma.

Effect of tranexamic acid by baseline risk of death in acute bleeding patients: a meta- analysis of individual patient-level data from 28 333 patients

Francois-Xavier Ageron, Angele Gayet-Ageron, Katharine Ker, Timothy J Coats, Haleema Shakur-Still, Ian Roberts, Antifibrinolytics Trials Collaboration

Br J Anaest. 2020 Jun;124(6):676-683

Background: Early administration of the antifibrinolytic drug tranexamic acid reduces death from bleeding in trauma and postpartum haemorrhage. We examined how the effectiveness and safety of antifibrinolytic drugs varies by the baseline risk of death as a result of bleeding.

Methods: We performed an individual patient-level data meta-analysis of randomised trials including more than 1000 patients that assessed antifibrinolytics in acute severe bleeding. We identified trials performed between January 1, 1946 and July 5, 2018 (PROSPERO, number

42016052155).

Results: Two randomised trials were selected where 28 333 patients received tranexamic acid treatment within 3 h after the onset of acute bleeding. Baseline characteristics to estimate the risk of death as a result of bleeding were divided into four categories: Low (0-5%), intermediate (6-10%), high (11-20%), and very high (>20%). Most patients had a low baseline risk of death as a result of bleeding (23 008 [81%]). Deaths as a result of bleeding occurred in all baseline risk categories with 240 (1%), 202 (8%), 232 (14%), and 357 (30%) deaths in the low-, intermediate-, high-, and very high-risk categories, respectively. The effectiveness of tranexamic acid did not vary by baseline risk when given within 3 h after bleeding onset (P=0.51 for interaction term). There was no increased risk of vascular occlusive events with tranexamic acid and it did not vary by baseline risk categories (P=0.25).

Conclusions: Tranexamic acid appears to be safe and effective regardless of baseline risk of death. Because many deaths are in patients at low and intermediate risk, tranexamic acid use should not be restricted to the most severely injured or bleeding patients.

 

U.S. Army Combat Medic eFAST Performance with a Novel Versus Conventional Transducers: A Randomized, Crossover Trial

Brian J Ahern, Jonathan D Monti, Jason F Naylor, Aaron J Cronin, Michael D Perreault Mil Med 2020 Jan 7;185(Suppl 1):19-24

Background: Point-of-injury extended focused assessment with sonography in trauma (eFAST) may identify life-threatening torso hemorrhage and expedite casualty evacuation. The purpose of this study was to compare combat medic eFAST performance between the novel and conventional ultrasound (US) transducers.

Methods: We conducted a randomized crossover trial. Medic participants, previously naïve to US, were randomized to the type of transducer first utilized. The primary outcome was eFAST completion time in seconds. Secondary outcomes included diagnostic accuracy, technical adequacy, and transducer ease-of-use rating.

Results: Forty medics performed 160 eFASTs. We found a statistically significant difference in eFAST completion times in favor of conventional transducers (304 vs. 358 s; P = 0.03). There was no statistically significant difference between the conventional and novel transducers in terms of diagnostic accuracy (97.7% vs. 96.0%; P = 0.25) and technical adequacy (65% vs.72.5%; P = 0.11). Median transducer ease-of-use rating (Likert 1-5 scale) was statistically significant in favor of the conventional transducers (5 vs. 4; P = < 0.001).

Conclusions: Extended focused assessment with sonography in trauma exam times was faster with the conventional transducers. Combat medics performed diagnostically accurate eFASTs with both transducer types in a simulated aid station setting after a brief training intervention.

Conventional transducers were rated higher for ease-of-use.

Whole Blood Administration: Comparison of In Vitro Platelet Function of Pressure Bag, Pressure Bag With Fluid Warming Device, and Rapid Infuser Methods

Tiffany Alley, Gigi Taylor, Amy Owens, James W Goodin, Niki Rasnake, Brian J Daley, Christopher T Clark 

J Trauma Nurs. Nov/Dec 2020;27(6):351-354 

Background: Use of low-titer group O whole blood for emergent transfusion of patients with unknown blood type became AABB approved in January 2018. Since that time, there is increasing use of whole blood in massive transfusion protocols. Whole blood stored at refrigerator temperature (2-4 °C) contains functional platelets that some research proposes may provide better clot dynamics than standard platelets, which are stored at room temperature (20-24 °C). Conventional teaching does not promote infusion of platelet products with pressure or warming, due to concerns of activation and subsequent inactivity of the infused platelets. Although a few reports found no significant changes in platelet function with warming or pressure during infusion of conventional room-temperature-stored platelets, there is limited data to support use of warming or pressure for infusion of whole blood products containing cold-stored platelets. 

Methods: This study design is to evaluate and compare three commonly used methods of administering blood products in a massive transfusion setting for their potential effects on platelets contained within whole blood units (pressure bag alone, pressure bag with fluid warming line, and rapid infuser). 

Results: Platelet function of 10 units tested pre- and post-infusion by thromboelastography (TEG) and platelet aggregation studies found no significant difference in platelet activity pre- and post-infusion with any of the three methods evaluated. 

Conclusions: This study supports the use of rapid infuser or pressure bag devices (with or without warming) as acceptable for infusion of whole blood products. Infusion of whole blood with warming is preferable to prevent potential transfusion-associated hypothermia.

Hemorrhage Control: Lessons Learned From the Battlefield Use of Hemostatic Agents That Can Be Applied in a Hospital Setting

Herman A Allison

Crit Care Nurs Q Apr/Jun 2019;42(2):165-172

Uncontrolled blood loss is a major cause of preventable death worldwide. A severe injury can occur anywhere at any time. Controlling blood loss is an important issue for patient care in the hospital setting. Through the casualties of war, the lifesaving value of quick interventions was developed. Since 2001, new hemostatic agents have advanced the benefits of controlling blood loss. There are unforgettable lessons learned in the preventable deaths of many soldiers and should be passed on to the next generation of health care providers, to include all hospitals up to level I trauma hospitals. This article covers the current hemostatic agents that have been used for more than 17 years on the battlefield and are slowly making their way into the hospital settings. The hemostatic agents covered include QuikClot Combat Gauze, QuikClot Control+, WoundClot Hemostatic Gauze, HemCon Nasal Plug, and RevMedx's XSTAT hemostatic device. The standard of care should not be affected by the location of a patient, whether that patient is in a remote village overseas, on the battlefield, a rural farm, or at a major metropolitan hospital here in the United States.

Prehospital transfusion of low titer cold-stored whole blood through the intraosseous route in a trauma patient with hemorrhagic shock

Raviv Allon, Danny Epstein , Itai Shavit Transfusion 2020 Apr;60(4):875-878

Abstract

Background: Damage control resuscitation, avoidance of dilutional coagulopathy, and increased blood component therapy reduce mortality after major trauma hemorrhage. Improved outcomes seen in recent warfare have placed whole blood as the preferred product for resuscitation of severe traumatic hemorrhage. As of 2018, flight physicians of the Israeli Airborne Combat Search and Rescue Unit (ACSRU) treat these patients with low titer cold-stored O-positive whole blood (LTCSO+ WB). Intraosseous (IO) is the preferred route if intravenous access is not available. To date, no study has described the administration of LTCSO+ WB via the IO route in the prehospital setting.

Case report: We present a case of whole blood transfusion via the IO route in a 30-year-old car accident patient who suffered major injuries and developed severe hemorrhagic shock.

Intravenous access could not be obtained at the scene. En route, two units of LTCSO+ WB were administered, using an IO hand drill, and the patient's hemodynamic status improved. The patient survived the injury with a good outcome.

Conclusion: This is the first report of whole blood infusion via the IO route in traumatic hemorrhagic shock in the prehospital setting. Our positive experience suggests that this approach may have a role in hemorrhagic trauma patients when intravenous access cannot be obtained.

Early Tranexamic Acid Administration After Traumatic Brain Injury Is Associated With Reduced Syndecan-1 and Angiopoietin-2 in Patients With Traumatic Intracranial Hemorrhage

Taylor N Anderson, Holly E Hinson, Elizabeth N Dewey, Elizabeth A Rick, Martin A Schreiber, Susan E Rowell

J Head Trauma Rehabil. Sep/Oct 2020;35(5):317-323 

Objective: To evaluate the effect of early tranexamic acid (TXA) administration on circulating markers of endotheliopathy.

Setting: Twenty trauma centers in the United States and Canada.

Participants: Patients with moderate-to-severe traumatic brain injury (TBI) (MS-TBI) and intracranial hemorrhage who were not in shock (systolic blood pressure ≥90 mm Hg).

Design: TXA (2 g) or placebo administered prior to hospital arrival, less than 2 hours postinjury. Blood samples and head computed tomographic scan collected upon arrival. Plasma markers measured using Luminex analyte platform. Differences in median marker levels evaluated using t tests performed on log-transformed variables. Comparison groups were TXA versus placebo and less than 45 minutes versus 45 minutes or more from time of injury to treatment administration.

Main measures: Plasma levels of angiopoietin-1, angiopoietin-2, syndecan-1, thrombomodulin, thrombospondin-2, intercellular adhesion molecule 1, vascular adhesion molecule 1.

Results: Demographics and Injury Severity Score were similar between the placebo (n = 129) and TXA (n = 158) groups. Levels of syndecan-1 were lower in the TXA group (median [interquartile range or IQR] = 254.6 pg/mL [200.7-322.0] vs 272.4 pg/mL [219.7-373.1], P = .05. Patients who received TXA less than 45 minutes postinjury had significantly lower levels of angiopoietin-2 (median [IQR] = 144.3 pg/mL [94.0-174.3] vs 154.6 pg/mL [110.4-209.8], P = .05). No differences were observed in remaining markers.

Conclusions: TXA may inhibit early upregulation of syndecan-1 and angiopoietin-2 in patients with MS-TBI, suggesting attenuation of protease-mediated vascular glycocalyx breakdown. The findings of this exploratory analysis should be considered preliminary and require confirmation in future studies.

Severity of hemorrhage and the survival benefit associated with plasma: Results from a randomized prehospital plasma trial

Vincent P Anto, Frank X Guyette, Joshua Brown, Brian Daley, Richard Miller, Brian Harbrecht, Jeffrey Claridge, Herb Phelan, Matthew Neal, Raquel Forsythe, Brian Zuckerbraun, Jason Sperry, PAMPer study group 

J Trauma Acute Care Surg 2020 Jan;88(1):141-147 

Abstract

Background: Recent randomized clinical trial evidence demonstrated a survival benefit with the use of prehospital plasma in patients at risk of hemorrhagic shock. We sought to characterize the survival benefit associated with prehospital plasma relative to the blood transfusion volume over the initial 24 hours. We hypothesized that the beneficial effects of prehospital plasma would be most robust in those with higher severity of hemorrhage.

Methods: We performed a prespecified secondary analysis using data derived from a prospective randomized prehospital plasma trial. Blood component transfusion volumes were recorded over the initial 24 hours. Massive transfusion (MT) was defined a priori as receiving ≥10 units of red cells in 24 hours. We characterized the 30-day survival benefit of prehospital plasma and the need for MT and overall 24-hour red cell transfusion volume utilizing Kaplan- Meier survival analysis and Cox proportional hazard regression.

Results: There were 501 patients included in this analysis with 230 randomized to prehospital plasma with 104 patients requiring MT. Mortality in patients who received MT were higher compared with those that did not (MT vs. NO-MT, 42% vs. 26%, p = 0.001). Kaplan-Meier survival curves demonstrated early separation in the NO-MT subgroup (log rank p = 0.008) with no survival benefit found in the MT group (log rank p = 0.949). Cox regression analysis verified these findings. When 24-hour red cell transfusion was divided into quartiles, there was a significant independent association with 30-day survival in patients who received 4 to 7 units (hazard ratio, 0.33, 95% confidence interval, 0.14-0.80, p = 0.013).

Conclusion: The survival benefits of prehospital plasma was demonstrated only in patients with red cell requirements below the transfusion level of MT. Patients who received 4 to 7 units of red cells demonstrated the most robust independent survival benefit attributable to prehospital plasma transfusion. Prehospital plasma may be most beneficial in those patients with moderate transfusion requirements and mortality risk.

Level of evidence: Therapeutic, Level I

An Applied Test of Knowledge Translation Methods Using a Mobile Health Solution Christina M Armstrong, Robert P Ciulla, Suzanne A Williams, Logan J Micheel

Mil Med 2020 Jan 7;185(Suppl 1):526-535 

Introduction: The study's objectives were to improve providers' knowledge of mobile health core competencies; increase providers' knowledge and clinical use of the Virtual Hope Box (VHB) mobile app as an evidence-based treatment tool; and test elements of a structured knowledge translation paradigm.

Materials and methods: knowledge translation best practices were integrated into a training workshop with the goal to increase provider adoption of the VHB. Providers were trained at three sites and provided feedback before the training, post-training, and at 3, 6, and 12 months following the training.

Results: Pretraining, <22% of respondents indicated that they had used the VHB in clinical practice; post-training, 89% of respondents reported their intent to use the VHB. At 3 and 6 months, 82% of evaluation respondents indicated actual use of the VHB.

Conclusions: Using a public-facing technology, this study successfully integrated knowledge translation methods within an existing provider training program. Implementation planning should be deliberate and consider a target site's capacity for new ideas and potential adoption barriers. Lessons learned have implications for future efforts to bridge the gap between research and practice in improving the quality and impact of clinical care.

How do I implement a whole blood-based blood preparedness program in a small rural hospital?

Torunn O Apelseth, Geir Strandenes, Einar K Kristoffersen, Kristin G Hagen, Hanne Braathen, Tor Hervig

 Transfusion. 2020 Dec;60(12):2793-2800

 Abstract 

Civilian and military guidelines recommend balanced transfusion to patients with life-threatening bleeding. Early start of transfusion has shown improved survival. Thus, a balanced blood inventory must be available in all levels of health care to ensure early stabilization and damage control resuscitation of patients with bleeding. Whole blood has been reintroduced as a blood product for massive bleeding situations because it affords plasma, red blood cells, and platelets in a balanced ratio in a logistically advantageous way. In this article, we describe how to establish a whole blood-based blood preparedness program in a small rural hospital with limited resources. We present an implementation tool kit, which includes discussions on whole blood program strategies and the process of developing detailed procedures on donor selection, collection, storage, and transfusion management of whole blood. The importance of training and audit of the routines is highlighted, and establishment of an emergency walking blood bank is discussed. We conclude that implementation of a whole blood program is achievable in small rural hospitals and recommend that rural health care facilities at all treatment levels enable early balanced transfusion for patients with life-threatening bleeding by establishing protocols for whole blood-based preparedness.

Prehospital Trauma Scene and Transport Times for Pediatric and Adult Patients

Nicklaus P Ashburn, Nella W Hendley, Ryan M Angi, Andrew B Starnes, R Darrell Nelson, Henderson D McGinnis, James E Winslow, David M Cline, Brian C Hiestand, Jason P Stopyra

West J Emerg Med 2020 Feb 21;21(2):455-462 

Introduction: Increased out-of-hospital time is associated with worse outcomes in trauma. Sparse literature exists comparing prehospital scene and transport time management intervals between adult and pediatric trauma patients. National Emergency Medical Services guidelines recommend that trauma scene time be less than 10 minutes. The objective of this study was to examine prehospital time intervals in adult and pediatric trauma patients.

Methods: We performed a retrospective cohort study of blunt and penetrating trauma patients in a five-county region in North Carolina using prehospital records. We included patients who were transported emergency traffic directly from the scene by ground ambulance to a Level I or Level II trauma center between 2013-2018. We defined pediatric patients as those less than 16 years old. Urbanicity was controlled for using the Centers for Medicare and Medicaid's Ambulance Fee Schedule. We performed descriptive statistics and linear mixed-effects regression modeling.

Results: A total of 2179 records met the study criteria, of which 2077 were used in the analysis. Mean scene time was 14.2 minutes (95% confidence interval [CI], 13.9-14.5) and 35.3% (n = 733) of encounters had a scene time of 10 minutes or less. Mean transport time was 17.5 minutes (95% CI, 17.0-17.9). Linear mixed-effects regression revealed that scene times were shorter for pediatric patients (p<0.0001), males (p=0.0016), penetrating injury (p<0.0001), and patients with blunt trauma in rural settings (p=0.005), and that transport times were shorter for males (p = 0.02), non-White patients (p<0.0001), and patients in urban areas (p<0.0001).

Conclusion: This study population largely missed the 10-minute scene time goal. Demographic and patient factors were associated with scene and transport times. Shorter scene times occurred with pediatric patients, males, and among those with penetrating trauma. Additionally, suffering blunt trauma while in a rural environment was associated with shorter scene time.

Males, non-White patients, and patients in urban environments tended to have shorter transport times. Future studies with outcomes data are needed to identify factors that prolong out-of- hospital time and to assess the impact of out-of-hospital time on patient outcomes.

Whole blood transfusion versus component therapy in adult trauma patients with acute major haemorrhage

Pascale Avery, Sarah Morton Harriet Tucker, Laura Green, Anne Weaver, Ross

Davenport Emerg Med J 2020 Jun;37(6):370-378 

Objective: In the era of damage control resuscitation of trauma patients with acute major haemorrhage, transfusion practice has evolved to blood component (component therapy) administered in a ratio that closely approximates whole blood (WB). However, there is a paucity of evidence supporting the optimal transfusion strategy in these patients. The primary objective was therefore to establish if there is an improvement in survival at 30 days with the use of WB transfusion compared with blood component therapy in adult trauma patients with acute major haemorrhage.

Methodology: A systematic literature search was performed on 15 December 2019 to identify studies comparing WB transfusion with component therapy in adult trauma patients and mortality at 30 days. Studies which did not report mortality were excluded. Methodological quality of included studies was interpreted using the Cochrane risk of bias tool, and rated using the Grading of Recommendations Assessment, Development and Evaluation approach.

Results: Search of the databases identified 1885 records, and six studies met the inclusion criteria involving 3255 patients. Of the three studies reporting 30-day mortality (one randomised controlled trial (moderate evidence) and two retrospective (low and very low evidence, respectively)), only one study demonstrated a statistically significant difference between WB and component therapy, and two found no statistical difference. Two retrospective studies reporting in-hospital mortality found no statistical difference in unadjusted mortality, but both reported statistically significant logistic regression analyses demonstrating that those with a WB transfusion strategy were less likely to die.

Conclusion: Recognising the limitations of this systematic review relating to the poor-quality evidence and limited number of included trials, it does not provide evidence to support or reject use of WB transfusion compared with component therapy for adult trauma patients with acute major haemorrhage.

Practical Considerations for a Military Whole Blood Program Marshall Bahr, Andrew P Cap, Devin Dishong Mark H Yazer

Mil Med 2020 Aug 14;185(7-8):e1032-e1038

Introduction: Prehospital care in the combat environment has always been of great importance to the U.S. military, and trauma resuscitation has remained a cornerstone. More evidence continues to demonstrate the advantages of intervention with early transfusion of blood products at the point of injury. The military has recognized these benefits; as such, the Department of Defense Joint Trauma System and the Committee on Tactical Combat Casualty Care have developed new advanced resuscitation guidelines, which now encourage the use of whole blood (WB) in the prehospital setting.

Materials and methods: This general review of peer-reviewed journal articles was performed through an extensive electronic search from the databases of PubMed Central (MEDLINE) and the Cochrane Library.

Results: Based on this literature search, the current evidence suggests that transfusion with WB is safe and efficacious. Additionally, soldier function is preserved after donating fresh WB in the field. Currently, the collection and implementation of WB is accomplished through several different protocol-driven techniques.

Conclusion: WB has become the favored transfusion product as it provides all of the components of blood in a convenient package that is easy to store and transport. Specifically, group O WB containing low titers of anti-A and -B antibodies has become the transfusion product of choice, offering the ability to universally fluid resuscitate patients despite not knowing their blood group. This new ability to obtain low titer group O WB has transformed the approach to the management of hemorrhagic shock in the prehospital combat environment.

Prehospital Whole Blood Resuscitation Reduces Fluid Requirement While Maintaining Critical Physiology in a Model of Penetrating Traumatic Brain Injury and Hemorrhage: Implications on Resource-Limited Combat Casualty Care

 Zachary S Bailey, Lai Yee Leung, Xiaofang Yang, Katherine Cardiff, Janice Gilsdorf, Deborah Shear, Patrick M Kochanek

 Shock. 2021 Apr 1;55(4):545-553

 Abstract 

Prehospital resuscitation using whole blood (WB) is the standard of care for hemorrhagic shock (HS) but there is no consensus recommendation for resuscitation in the presence of traumatic brain injury (TBI) due to a lack of sufficient evidence. In order to evaluate the optimal resuscitation strategies for TBI+HS, Sprague-Dawley rats were randomized into four groups based on resuscitation fluid and prehospital mean arterial pressure (MAP) threshold (n = 9-10/group): Lactated Ringer's (LR)-60 mm Hg (LR60), LR-70 mm Hg (LR70), WB-60 mm Hg (WB60), WB-70 mm Hg (WB70). All groups received a frontal penetrating ballistic-like brain injury followed by a 35-min period of HS. During the prehospital phase, rats received an initial bolus of resuscitation fluid (WB or LR) followed by LR as needed to maintain MAP above the designated threshold for 90 min. During the in-hospital phase, rats received definitive resuscitation with shed WB. Physiological parameters were recorded continuously and cerebral edema was measured at 3 and 24 h postinjury. The WB60 group demonstrated a significantly lower prehospital fluid requirement compared WB70, LR60, and LR70 (P < 0.05). Compared to the respective LR groups, both the WB60 and WB70 groups also demonstrated improved MAP, cerebral perfusion pressure, brain tissue oxygen tension, and cerebral edema. The edema benefits were observed at 3 h, but not 24 h postinjury, and were localized to the injury site. Together, these results provide evidence that prehospital WB resuscitation and lower MAP resuscitation thresholds can reduce the prehospital fluid requirement while still maintaining critical cerebral physiology in a model of HS and concomitant TBI.

Austere Resuscitative and Surgical Care in Support of Forward Military Operations-Joint Trauma System Position Paper

Jay B Baker, Maj D Marc Northern, Colin Frament, D Aaron Baker, Kyle Remick, Jason Seery, Lance Stephens, Stacy Shackelford, Jennifer Gurney

Mil Med. 2020 Nov 13;usaa358

No abstract available

First experience with the abdominal aortic and junctional tourniquet in prehospital traumatic cardiac arrest

 Fay Balian, Alan A Garner, Andrew Weatherall, Anna Lee 

Resuscitation. 2020 Nov;156:210-214 

Introduction: The Abdominal Aortic and Junctional Tourniquet (AAJT) increased systemic vascular resistance, mean arterial pressure, carotid blood flow and rate of return of spontaneous circulation (ROSC) in animals with hypovolaemic traumatic cardiac arrest (TCA). The objective of this study was to report the first experience of the use of the AAJT as part of a pre-hospital TCA algorithm. 

Methods: This is a descriptive case series of the use of the AAJT in patients with TCA in a civilian physician-led pre-hospital trauma service in Sydney, Australia between June 2015 to August 2019. Cases were identified and data sourced from routinely collected data sets within the retrieval service. 

Results: During the study, 44 TCAs were attended, 22 with AAJT application. Mean time (standard deviation) to AAJT application since last signs of life was 16 (9) min. Eighteen (16 males, 2 females) patients, with median age (interquartile range) of 40 (25-58) years, were included for analysis. Seventeen patients (94%) had blunt trauma. Sixteen patients (89%) were in TCA at the time of service contact, 11 (61%) had a change in electrical activity, 4 (22%) had ROSC, and of the 6 with documented end-tidal carbon dioxide, the mean rise was 24.0 mmHg (95% CI 12.6-35.4) (P = 0.003). Three patients (17%) had sustained ROSC on arrival to the Emergency Department. No patients survived to hospital discharge.

Conclusion: Physiological changes were demonstrated but there were no survivors. Further research focusing on faster application times may be associated with improved outcomes.

Ketamine as a Prehospital Analgesic: A Systematic Review (Need link)

Akhil Bansal, Matthew Miller, Ian Ferguson, Brian Burns Prehosp Disaster Med 2020 Jun;35(3):314-321 

Objective: Analgesia in the prehospital setting is an extremely important, yet controversial topic. Ketamine, a N-methyl D-aspartate (NMDA) receptor antagonist, has been commonly used in the prehospital setting, including recommendations by the US Department of Defense and by the Royal Australian College of Pain Medicine, despite the paucity of high-level evidence.

Methods: Accordingly, a review of the literature was conducted using several electronic medical literature databases from the earliest available records to the time at which the search was conducted (October 2018).

Results: The search strategy yielded a total of 707 unique papers, of which 43 were short-listed for full review, and ultimately, ten papers were identified as meeting all the relevant inclusion criteria. The included studies varied significantly in the prehospital context and in the means of administering ketamine. There was only low-grade evidence that ketamine offered a safe and effective analgesia when used as the only analgesic, and only low-grade evidence that it was as effective as alternative opioid options. However, there was moderate evidence that co- administration of ketamine with morphine may improve analgesic efficacy and reduce morphine requirement.

Conclusions: Overall, ketamine as a prehospital analgesic may be best used in combination with opioids to reduce opioid requirement. It is suggested that future studies should use a standardized approach to measuring pain reduction. Future studies should also investigate short-term side effects and long-term complications or benefits of prehospital ketamine.

Ketamine: a versatile tool for anesthesia and analgesia

William Barrett, Michael Buxhoeveden, Sabrina Dhillon 

Curr Opin Anaesthesiol. 2020 Oct;33(5):633-638. 

Abstract 

Purpose of review: Ketamine has been used for decades for a variety of indications. Beyond the historical benefits and effects of ketamine, newer developments have occurred worthy of an update. This review will discuss common uses and indications for ketamine in the perioperative setting, as well as highlight newer indications in recent years. 

Recent findings: Multiple studies have examined the use of ketamine in a variety of environments, as ketamine has become more popular in emergency rooms and ICUs. Ketamine may be particularly beneficial in management of burn patients, who often require multiple procedures over the course of their treatment. Ketamine's role in the ongoing opioid crisis has been of particular interest, with multiple studies evaluating its potential role in managing both acute and chronic pain conditions. Ongoing studies examining the role of ketamine in treatment of depressions show promise as well. 

Summary: Ketamine is regaining popularity in the field of anesthesia and beyond. New studies provide insight on the many indications and use that anesthesia providers may encounter during their perioperative care of patients. Ongoing research is needed to further elucidate ketamine's effects on the management of psychiatric conditions and potential indications for ketamine metabolites.

Decompression of Subdural Hematomas Using an Intraosseous Needle in the Emergency Department: A Case Series

Brett Barro, Scott Kobner, Ashkon Ansari

Clin Pract Cases Emerg Med. 2020 Aug;4(3):312-315

Introduction: Traumatic subdural hematomas beget significant morbidity and mortality if not rapidly decompressed. This presents a unique challenge to the emergency physician without immediate neurosurgical support. 

Case report: We report two cases of patients in Los Angeles County with traumatic subdural hematomas and clinical deterioration in the emergency department (ED) who were treated with decompression using an intraosseous needle drill. 

Discussion: We believe these cases represent the first use of this technique to temporize a subdural hematoma in the ED.

Tourniquet application by schoolchildren-a randomized crossover study of three commercially available models

Alaa El Bashtaly, Elene Khalil, Francois Méthot, Lawrence Ledoux-Hutchinson, Jeffrey M Franc, Valérie Homier 

J Trauma Acute Care Surg. 2021 Apr 1;90(4):666-672 

Background: Life-threatening hemorrhage is a major cause of preventable mortality in trauma. Studies have demonstrated the effectiveness and safety of commercial tourniquets when used by adult civilians. However, there are no data about tourniquet application by children.This study's goal is to determine which of three commercially available tourniquets is most effective when used by children. 

Methods: A randomized crossover study was conducted in four elementary schools in Montreal to compare three commercially available tourniquets. The study population is primary school children aged 10 to 12 years (5th-6th grade). A total of 181 students were invited to participate; 96 obtained parental approval and were recruited. Participants underwent a short 7-minute video training on the use of three commercial tourniquets and were subsequently given a 2-minute practice period. Students were evaluated on their ability to successfully apply the tourniquet and the time to complete application. After applying all three tourniquets, the students selected their favorite model. The primary outcome is the proportion of successful applications per tourniquet model. Secondary outcomes include time to successful application for each tourniquet model and tourniquet model preference. 

Results: The mechanical advantage tourniquet (MAT) outperformed the combat application tourniquet (CAT) and the stretch wrap and tuck tourniquet (SWATT) in terms of success rate (MAT, 67%; CAT, 44%; SWATT, 24%; p < 0.0001), time to application (MAT, 57 seconds; CAT, 80 seconds; SWATT, 90 seconds; p < 0.0001), and preference (MAT, 64%; CAT, 30%; SWATT, 6%; p < 0.0001). 

Conclusion: In this study, the MAT performs better in terms of success rate, time to application, and preference when used by school-aged children. This study can be helpful when facilities are purchasing tourniquets for use by students.

Topical tranexamic acid inhibits fibrinolysis more effectively when formulated with self-propelling particles

James R Baylis, Michael M Lee, Alexander E St John, Xu Wang, Eric Simonson, Massimo Cau, Amir Kazerooni, Vionarica Gusti, Matthew L Statz, Jeff S J Yoon, Richard T Liggins, Nathan J White, Christian J Kastrup 

J Thromb Haemost. 2019 Oct;17(10):1645-1654 

Background: Endogenous fibrinolytic activation contributes to coagulopathy and mortality after trauma. Administering tranexamic acid (TXA), an antifibrinolytic agent, is one strategy to reduce bleeding; however, it must be given soon after injury to be effective and minimize adverse effects. Administering TXA topically to a wound site would decrease the time to treatment and could enable both local and systemic delivery if a suitable formulation existed to deliver the drug deep into wounds adequately. 

Objectives: To determine whether self-propelling particles could increase the efficacy of TXA. 

Methods: Using previously developed self-propelling particles, which consist of calcium carbonate and generate CO2 gas, TXA was formulated to disperse in blood and wounds. The antifibrinolytic properties were assessed in vitro and in a murine tail bleeding assay. Self-propelled TXA was also tested in a swine model of junctional hemorrhage consisting of femoral arteriotomy without compression. 

Results: Self-propelled TXA was more effective than non-propelled formulations in stabilizing clots from lysis in vitro and reducing blood loss in mice. It was well tolerated when administered subcutaneously in mice up to 300 to 1000 mg/kg. When it was incorporated in gauze, four of six pigs treated after a femoral arteriotomy and without compression survived, and systemic concentrations of TXA reached approximately 6 mg/L within the first hour. 

Conclusions: A formulation of TXA that disperses the drug in blood and wounds was effective in several models. It may have several advantages, including supporting local clot stabilization, reducing blood loss from wounds, and providing systemic delivery of TXA. This approach could both improve and simplify prehospital trauma care for penetrating injury.

Combat Application Tourniquet fares well in a chemical, biological, radiological or nuclear dress state

Alastair Beaven, E Sellon, M Ballard, P Parker BMJ Mil Health 2020 Feb 20;jramc-2019-001261 

Abstract

Introduction: There is a need for a military tourniquet to control catastrophic haemorrhage in a chemical, biological, radiological or nuclear (CBRN) threat environment. No published data exist as to the efficacy of tourniquets while wearing British military CBRN individual protective equipment (IPE).

Methods: 12 volunteers from the counter CBRN instructors' course allowed testing on 24 legs. A Combat Application Tourniquet (C-A-T) was applied to all volunteers at the level of the midthigh. 12 legs were tested while wearing CBRN IPE (both operator and simulated casualty), and the control group of 12 legs was tested while wearing conventional combat dress state (both operator and simulated casualty). The order of leg laterality and dress state were sequenced according to a prerandomised system. Efficacy was measured via use of an ultrasound probe at the popliteal artery. Tourniquets were considered effective if arterial flow was completely occluded on ultrasound imaging. Data were collected on time to successful application, failure of tourniquets and pain scores as rated by the visual analogue scale (1-10).

Results: There were no failures of tourniquet application in the CBRN group, and two failures (17%) in the control group. Failures were pain threshold exceeded (n=1) and tourniquet internal strap failure (n=1). The mean application time for the CBRN group was 28.5 s (SD 11.7) and

23.7 s (SD 9.8) for the conventional combat group. There was no statistically significant difference (p=0.27). The median CBRN pain score was 2.0 (IQR 2.0-3.5). The median control pain score was 4.0 (IQR 3-6). This was a statistically significant difference (p=0.002).

Conclusion: C-A-Ts applied to simulated casualties in CBRN IPE at the midthigh are at least as efficacious as those applied to the midthigh in a conventional combat dress state. The pain experienced was less in CBRN IPE than when in a conventional combat dress state.

Intravenous Hydroxocobalamin Versus Hextend Versus Control for Class III Hemorrhage Resuscitation in a Prehospital Swine Model

Vikhyat S Bebarta, Normalynn Garrett , Susan Boudreau , Maria Castaneda Mil Med 2018 Nov 5;183(11-12):e721-e729 

Abstract

Background: Hydroxyethyl starch (Hextend) has been used for hemorrhagic shock resuscitation, however, hydroxyethyl starch may be associated with adverse outcomes.

Objective: To compare systolic blood pressure (sBP) in animals that had 30% of their blood volume removed and treated with intravenous hydroxocobalamin, hydroxyethyl starch, or no fluid.

Methods: Twenty-eight swine (45-55 kg) were anesthetized and instrumented with continuous femoral and pulmonary artery pressure monitoring. Animals were hemorrhaged 20 mL/kg over 20 minutes and then administered 150 mg/kg IV hydroxocobalamin in 180 mL saline, 500 mL hydroxyethyl starch, or no fluid and monitored for 60 minutes. Data were modeled using repeated measures multivariate analysis of variance.

Results: There were no significant differences before treatment. At 20 minutes after hemorrhage, there was no significant difference in mean sBP between treated groups, however, control animals displayed significantly lower mean sBP (p < 0.001). Mean arterial pressure and heart rate improved in the treated groups but not in the control group (p < 0.02). Prothrombin time was longer and platelet counts were lower in the Hextend group (p < 0.05). Moreover, thromboelastography analysis showed longer clotting (K) times (p < 0.05) for the hydroxyethyl starch-treated group.

Conclusion: Hydroxocobalamin restored blood pressure more effectively than no treatment and as effectively as hydroxyethyl starch but did not adversely affect coagulation.

Death Ignores the Golden Hour The Argument for Mobile, Farther-Forward Surgery(Need link)

Brian C. Beldowicz, Michael Bellamy, Robert Modlin

MILITARY REVIEW 2020; March-April 2020: 39-48 

Although the footprint of medical resources has significantly contracted in recent years, the geography of ongoing operations has not. As a result, at-risk soldiers find themselves reliant on more tenuous limbs of medical support, far removed from the meticulously orchestrated medical evacuation (medevac) rings once deemed an operational imperative. The first hour after the occurrence of a traumatic injury is considered the most critical for emergency stabilization of a casualty. This “Golden Hour” concept establishes a serviceable standard for the distribution of fixed medical resources supporting areas of operation. However, the Golden Hour paradigm is insufficient for large-scale combat operations (LSCO), specifically when planning medical support for those offensive operations associated with the highest risk to force or those conducted in movement-restricted environments where timely medevac is not guaranteed. In order to provide ground force commanders with options for risk reduction consistent with best medical practice, medical planning will need to recalibrate from the prevailing Golden Hour paradigm to a more deliberate mission support model. Planners must consider operational importance, asymmetric distribution of risk to force, and available surgical assets’ capacity to influence preventable combat mortality and improve the efficiency of the casualty care system.

Randomized trial of the i-gel supraglottic airway device versus tracheal intubation during out of hospital cardiac arrest (AIRWAYS-2): Patient outcomes at three and six months

Jonathan R Benger, Michelle J Lazaroo, Madeleine Clout, Sarah Voss, Sarah Black, Stephen J Brett, Kim Kirby, Jerry P Nolan, Barnaby C Reeves, Maria Robinson, Lauren J Scott, Helena Smartt, Adrian South, Jodi Taylor, Matthew Thomas, Sarah Wordsworth, Chris A Rogers 

Resuscitation. 2020 Dec;157:74-82 

Aim: The AIRWAYS-2 cluster randomised controlled trial compared the i-gel supraglottic airway device (SGA) with tracheal intubation (TI) as the first advanced airway management (AAM) strategy used by Emergency Medical Service clinicians (paramedics) treating adult patients with non-traumatic out-of-hospital cardiac arrest (OHCA). It showed no difference between the two groups in the primary outcome of modified Rankin Scale (mRS) score at 30 days/hospital discharge. This paper reports outcomes to 6 months. 

Methods: Paramedics from four ambulance services in England were randomised 1:1 to use an i-gel SGA (759 paramedics) or TI (764 paramedics) as their initial approach to AAM. Adults who had a non-traumatic OHCA and were attended by a participating paramedic were enrolled automatically under a waiver of consent. Survivors were invited to complete questionnaires at three and six months after OHCA. Outcomes were analysed using regression methods. 

Results: 767/9296 (8.3%) enrolled patients survived to 30 days/hospital discharge and 317/767 survivors (41.3%) consented and were followed-up to six months. No significant differences were found between the two treatment groups in the primary outcome measure (mRS score: 3 months: odds ratio (OR) for good recovery (i-gel/TI, OR) 0.89, 95% CI 0.69-1.14; 6 months OR 0.91, 95% CI 0.71-1.16). EQ-5D-5L scores were also similar between groups and sensitivity analyses did not alter the findings. 

Conclusion: There were no statistically significant differences between the TI and i-gel groups at three and six months. We therefore conclude that the initially reported finding of no significant difference between groups at 30 days/hospital discharge was sustained when the period of follow-up was extended to six months.

Prehospital fluid administration in patients with severe traumatic brain injury: A systematic review and meta-analysis 

S F Bergmans, P Schober, L A Schwarte, S A Loer, S M Bossers 

Injury. 2020 Nov;51(11):2356-2367 

Background: Prehospital management of severe traumatic brain injury (TBI) focuses on preventing secondary brain injury. Therefore, hypotension should be prevented, or if present, should be promptly treated in order to maintain optimal cerebral perfusion pressure. Fluid resuscitation is a traditional mainstay in the prehospital treatment of hypotension, however, the choice of fluid type that is to be administered in the prehospital setting is the subject of an on-going debate. This systematic review and meta-analysis was therefore performed to assess the effect of different fluid types on outcome in patients with severe TBI. 

Methods: PubMed, Embase and Web of Science were searched for articles up to March 2020. Studies comparing two or more prehospital administered fluid types with suspected or confirmed severe TBI were deemed eligible for inclusion. Studied outcomes were mortality and (extended) Glasgow Outcome Scale (GOS). The meta-analysis tested for differences in survival between hypertonic saline (HTS) and normotonic crystalloids (i.e. normal saline or Lactated Ringer's) and between hypertonic saline with dextran (HSD) and normotonic crystalloids. The systematic review is registered in the PROSPERO register with number CRD42020140423. 

Results: This literature search yielded a total of 519 articles, of which 12 were included in the systematic review and 6 were included in the meta-analysis. Eleven studies found no statistically significant difference in survival between patients treated with different fluid types (e.g. normal saline and hypertonic saline). All studies assessing neurological outcome, measured through (extended) GOS, found no statistically significant difference between different fluid types. Meta-analysis showed no better survival for patients treated with HSD, when compared to normotonic crystalloids (overall RR 0.99, 95% CI 0.93-1.06). Moreover, HTS compared to normotonic crystalloids does not result in a better survival (overall RR 1.04, 95% CI 0.97-1.12). 

Conclusions: This systematic review and meta-analysis did not demonstrate a survival or neurological benefit for one specific fluid type administered in the prehospital setting.

A prospective randomised trial to compare three insertion techniques for i-gel™ placement: Standard, reverse, and rotation 

Mamta Bhardwaj, Suresh K Singhal, Rashmi, Amit Dahiya 

Indian J Anaesth. 2020 Jul;64(7):618-623 

Background and aims: This prospective randomised study was done to compare standard, reverse, and rotation techniques of i-gel™ placement in terms of insertion characteristics and success rate. 

Material and methods: After institutional ethics committee approval, 135 patients aged 18-50 years, ASA I and II undergoing elective surgery under general anesthesia were included. After induction of anesthesia, i-gel™ was inserted by standard, reverse, and rotation technique in Groups I, II, and III, respectively. The primary objective was mean time of insertion. Secondary variables included ease of insertion, first attempt success rate, manoeuvres required, fiberoptic view of placement, oropharyngeal leak pressure, ease of placement of nasogastric tube, and complications if any. 

Results: Mean time of insertion was 18.04 ± 5.65 s, 15.00 ± 5.72 s and 16.12 ± 5.84 s for groups I, II, and III, respectively. Time taken for insertion was shortest and significantly lower (P = 0.048) for group II compared to group I. Insertion time was comparable between rest of groups. The overall success rate in groups I, II, and III were 91.1%, 95.6%, and 93.3% respectively (P = 0.7). The first attempt success rate was 82.2%, 89%, and 84.4% in groups I, II and III, respectively (P = 0.07). Manoeuvres were required in five (12.19%) patients in group I, four (9.30%) patients in group II, and three (7.14%) patients in group III (P = 0.602). Complications occurred in eight, three, and three patients in groups I, II, and III, respectively. 

Conclusion: All techniques of i-gel insertion are equally good and choice of technique depends upon the experience and comfort of the investigator with the particular technique.

Why do some trauma patients die while others survive? A matched-pair analysis based on data from Trauma Register DGU® 

Dan Bieler, Thomas Paffrath, Annelie Schmidt, Maximilian Völlmecke, Rolf Lefering, Martin Kulla, Erwin Kollig, Axel Franke, Sektion NIS of the German Trauma Society 

Chin J Traumatol. 2020 Aug;23(4):224-232 

Purpose: The mortality rate for severely injured patients with the injury severity score (ISS) ≥16 has decreased in Germany. There is robust evidence that mortality is influenced not only by the acute trauma itself but also by physical health, age and sex. The aim of this study was to identify other possible influences on the mortality of severely injured patients. 

Methods: In a matched-pair analysis of data from Trauma Register DGU®, non-surviving patients from Germany between 2009 and 2014 with an ISS≥16 were compared with surviving matching partners. Matching was performed on the basis of age, sex, physical health, injury pattern, trauma mechanism, conscious state at the scene of the accident based on the Glasgow coma scale, and the presence of shock on arrival at the emergency room. 

Results: We matched two homogeneous groups, each of which consisted of 657 patients (535 male, average age 37 years). There was no significant difference in the vital parameters at the scene of the accident, the length of the pre-hospital phase, the type of transport (ground or air), pre-hospital fluid management and amounts, ISS, initial care level, the length of the emergency room stay, the care received at night or from on-call personnel during the weekend, the use of abdominal sonographic imaging, the type of X-ray imaging used, and the percentage of patients who developed sepsis. We found a significant difference in the new injury severity score, the frequency of multi-organ failure, hemoglobine at admission, base excess and international normalized ratio in the emergency room, the type of accident (fall or road traffic accident), the pre-hospital intubation rate, reanimation, in-hospital fluid management, the frequency of transfusion, tomography (whole-body computed tomography), and the necessity of emergency intervention. 

Conclusion: Previously postulated factors such as the level of care and the length of the emergency room stay did not appear to have a significant influence in this study. Further studies should be conducted to analyse the identified factors with a view to optimising the treatment of severely injured patients. Our study shows that there are significant factors that can predict or influence the mortality of severely injured patients.

Examining the Learning Practice of Emergency Airway Management Within an Academic Medical Center: Implications for Training and Improving Outcomes 

Edward A Bittner, Ulrich Schmidt 

J Med Educ Curric Dev. 2020 Oct 14;7:2382120520965257 

Abstract 

Emergency airway management (EAM) is a "high stakes" clinical practice, associated with a significant risk of procedure-related complications and patient mortality. Learning within the EAM team practice is complex and challenging for trainees. Increasing concern for patient safety and changes in the structure of medical education have resulted in educational challenges and opportunities for improvement within the EAM team practice. This paper is divided into 3 sections that describe the past, present, and future of the EAM team learning practice within a large academic institution. Section 1 provides a brief overview of the evolution of the existing practice of EAM. Key features, goals, and challenges of the practice are outlined and a recently performed needs analysis to identify areas for improvement is described. Section 2 examines the underlying assumptions regarding learning within the existing practice and explores how these assumptions fit into major theories of learning. Section 3 proposes an idealized learning practice for the EAM team which includes the assumptions regarding learners, design of the learning environment, use of technology to enhance learning, and the means of assessment and measuring success. It is hoped that through this systematic exploration of the EAM team practice, learning efficacy and efficiency will be improved and remain adaptable for challenges in the future.

Cold-stored whole blood in a Norwegian emergency helicopter service: an observational study on storage conditions and product quality

Christopher Bjerkvig, Joar Sivertsen, Hanne Braathen, Turid Helen Felli Lunde, Geir Strandenes, Jörg Assmus, Tor Hervig, Andrew Cap, Einar K Kristoffersen, Theodor Fosse, Torunn Oveland Apelseth

Transfusion 2020 Jul;60(7):1544-1551 

Background: Increasing numbers of emergency medical service agencies and hospitals are developing the capability to administer blood products to patients with hemorrhagic shock. Cold- stored whole blood (WB) is the only single product available to prehospital providers who aim to deliver a balanced resuscitation strategy. However, there are no data on the safety and in vitro characteristics of prehospital stored WB. This study aimed to describe the effects on in vitro quality of storing WB at remote helicopter bases in thermal insulating containers.

Study design and methods: We conducted a two-armed single-center study. Twenty units (test) were stored in airtight thermal insulating containers, and 20 units (controls) were stored according to routine procedures in the Haukeland University Hospital Blood Bank. Storage conditions were continuously monitored during emergency medical services missions and throughout remote and blood bank storage. Hematologic and metabolic variables, viscoelastic properties, and platelet (PLT) aggregation were measured on Days 1, 8, 14, and 21.

Results: Storage conditions complied with the EU guidelines throughout remote and in-hospital storage for 21 days. There were no significant differences in PLT aggregation, viscoelastic properties, and hematology variables between the two groups. Minor significantly lower pH, glucose, and base excess and higher lactate were observed after storage in airtight containers.

Conclusion: Forward cold storage of WB is safe and complies with EU standards. No difference is observed in hemostatic properties. Minor differences in metabolic variables may be related to the anaerobic conditions within the thermal box.

The Evolution of Blood Transfusion in the Trauma Patient: Whole Blood Has Come Full Circle

Jonathan A Black, Virginia S Pierce, Jeffrey D Kerby, John B Holcomb Semin Thromb Hemost 2020 Mar;46(2):215-220 

Abstract

Whole blood transfusion in the United States dates back to the Civil War, and it was widely used in all major conflicts since World War I. To understand our current civilian transfusion practices and to anticipate future changes in trauma resuscitation, it is important to understand the series of decisions that led trauma surgeons away from whole blood resuscitation and toward component therapy. In this review, we examine the historical basis for blood transfusion in trauma and examine the recent literature and future directions pertaining to blood product resuscitation in hemorrhaging patients.

Tranexamic acid in emergency care Benjamin Bloom

 Eur J Emerg Med 2020 Apr;27(2):81-82

No abstract available

 

How to Stop the Bleed: First Care Provider Model for Developing Public Trauma Response Beyond Basic Hemorrhage Control

Joshua P Bobko, Dylan J Badin, Leila Danishgar, Kate Bayhan, Kevin J Thompson, William J Harris, R Todd Baldridge, Gerald R Fortuna Jr

West J Emerg Med. 2020 Feb 25;21(2):365-373 

Introduction: Since 2013, the First Care Provider (FCP) model has successfully educated the non-medical population on how to recognize life-threatening injuries and perform interventions recommended by the Committee for Tactical Emergency Casualty Care (C-TECC) and the Hartford Consensus in the disaster setting. Recent programs, such as the federal "Stop The Bleed" campaign, have placed the emphasis of public training on hemorrhage control. However, recent attacks demonstrate that access to wounded, recognition of injury, and rapid evacuation are equally as important as hemorrhage control in minimizing mortality. To date, no training programs have produced a validated study with regard to training a community population in these necessary principles of disaster response.

Methods: In our study, we created a reproducible community training model for implementation into prehospital systems. Two matched demographic groups were chosen and divided into "trained" and "untrained" groups. The trained group was taught the FCP curriculum, which the Department of Homeland Security recognizes as a Stop the Bleed program, while the untrained group received no instruction. Both groups then participated in a simulated mass casualty event, which required evaluation of multiple victims with varying degree of injury, particularly a patient with an arterial bleed and a patient with an airway obstruction.

Results: The objective measures in comparing the two groups were the time elapse until their first action was taken (T1A) and time to their solution of the simulation (TtS). We compared their times using one-sided t-test to demonstrate their responses were not due to chance alone. At the arterial bleed simulation, the T1A for the trained and untrained groups, respectively, were 34.75 seconds and 111 seconds (p-value = .1064), while the TtS were 3 minutes and 33 seconds in the trained group and eight minutes in the untrained groups (physiologic cutoff) (p-value = .0014). At the airway obstruction simulation, the T1A for the trained and untrained groups, respectively, were 20.5 seconds and 43 seconds (p-value = .1064), while the TtS were 32.6 seconds in the trained group and 7 minutes and 3 seconds in the untrained group (p-value = .0087). Simulation values for recently graduated nursing students and a local fire department engine company (emergency medical services [EMS]) were also given for reference. The trained group's results mirrored times of EMS.

Conclusion: This study demonstrates an effective training model to civilian trauma response, while adhering to established recommendations. We offer our model as a potential solution for accomplishing the Stop The Bleed mission while advancing the potential of public disaster response.

Novel use of XSTAT 30 for mitigation of lethal non-compressible torso hemorrhage in swine

Alicia M Bonanno, Todd L Graham, Lauren N Wilson, James D Ross

PLoS One. 2020 Nov 18;15(11):e0241906 

Background: Management of Non-Compressible Torso Hemorrhage (NCTH) consists primarily of aortic occlusion which has significant adverse outcomes, including ischemia-reperfusion injury, in prolonged field care paradigms. One promising avenue for treatment is through use of RevMedx XSTAT 30™ (an FDA approved sponge-based dressing utilized for extremity wounds). We hypothesized that XSTAT 30™ would effectively mitigate NCTH during a prolonged pre-hospital period with correctable metabolic and physiologic derangements.

Methods and findings: Twenty-four male swine (53±2kg) were anesthetized, underwent line placement, and splenectomy. Animals then underwent laparoscopic transection of 70% of the left lobe of the liver with hemorrhage for a period of 10min. They were randomized into three groups: No intevention (CON), XSTAT 30™-Free Pellets (FP), and XSTAT 30™-Bagged Pellets (BP). Animals were observed for a pre-hospital period of 180min. At 180min, animals underwent damage control surgery (DCS), balanced blood product resuscitation and removal of pellets followed by an ICU period of 5 hours. Postoperative fluoroscopy was performed to identify remaining pellets or bags. Baseline physiologic and injury characteristics were similar. Survival rates were significantly higher in FP and BP (p<0.01) vs CON. DCS was significantly longer in FP in comparison to BP (p = 0.001). Two animals in the FP group had pellets discovered on fluoroscopy following DCS. There was no significant difference in blood product or pressor requirements between groups. End-ICU lactates trended to baseline in both FP and BP groups.

Conclusions: While these results are promising, further study will be required to better understand the role for XSTAT in the management of NCTH.

Learner-centered Survey of Point-of-care Ultrasound Training, Competence, and Implementation Barriers in Emergency Medicine Training Programs in India 

Keith S Boniface, Aaran Drake, Matthew Pyle, Fabith Moideen, Sanjay Mehta, Venugopal Poovathumparambil, Hamid Shokoohi, Katherine Douglass 

AEM Educ Train. 2019 Dec 27;4(4):387-394 

Background: Point-of-care ultrasound (POCUS) is important to the practice of emergency medicine (EM), but requires training to achieve competence. The purpose of this study was to describe the current state of POCUS practice and perceived barriers to the implementation in EM training programs in India. 

Methods: A cross-sectional survey consisting of 28 questions was administered to 378 faculty and residents in postgraduate EM training programs across India. 

Results: Data were collected from 159 physicians from 16 institutions; 76% of them were EM residents, with a response rate of 42%. Respondents overwhelmingly reported high interest (91%) in learning POCUS topics. Respondents identified highest levels of comfort with the performance and interpretation of trauma ultrasound (US) and echocardiography. Conversely, there was a scarce interest and low levels of competence in performing obstetric US, which may be a result of the practice of triaging these complaints to obstetricians and gynecologists. Lack of US equipment and dedicated training were the highest rated barriers by a significant margin, which 56% of respondents ranked as "very important." 

Conclusions: While significant interest in POCUS exists among the Indian EM physicians, comfort and competence were limited to trauma and echocardiography applications. Expansion of and comfort with POCUS use in these settings may be sought through improvement of access to US equipment and a dedicated US curriculum.

Association Between Prehospital Tranexamic Acid Administration and Outcomes of Severe Traumatic Brain Injury

Sebastiaan M Bossers, Stephan A Loer, Frank W Bloemers, Dennis Den Hartog, Esther M M Van Lieshout, Nico Hoogerwerf, Joukje van der Naalt, Anthony R Absalom, Saskia M Peerdeman, Lothar A Schwarte , Christa Boer, Patrick Schober, BRAIN-PROTECT collaborators 

JAMA Neurol. 2021 Mar 1;78(3):338-345 

Importance: The development and expansion of intracranial hematoma are associated with adverse outcomes. Use of tranexamic acid might limit intracranial hematoma formation, but its association with outcomes of severe traumatic brain injury (TBI) is unclear. 

Objective: To assess whether prehospital administration of tranexamic acid is associated with mortality and functional outcomes in a group of patients with severe TBI. 

Design, setting, and participants: This multicenter cohort study is an analysis of prospectively collected observational data from the Brain Injury: Prehospital Registry of Outcome, Treatments and Epidemiology of Cerebral Trauma (BRAIN-PROTECT) study in the Netherlands. Patients treated for suspected severe TBI by the Dutch Helicopter Emergency Medical Services between February 2012 and December 2017 were included. Patients were followed up for 1 year after inclusion. Data were analyzed from January 10, 2020, to September 10, 2020. 

Exposures: Administration of tranexamic acid during prehospital treatment. 

Main outcomes and measures: The primary outcome was 30-day mortality. Secondary outcomes included mortality at 1 year, functional neurological recovery at discharge (measured by Glasgow Outcome Scale), and length of hospital stay. Data were also collected on demographic factors, preinjury medical condition, injury characteristics, operational characteristics, and prehospital vital parameters. 

Results: A total of 1827 patients were analyzed, of whom 1283 (70%) were male individuals and the median (interquartile range) age was 45 (23-65) years. In the unadjusted analysis, higher 30-day mortality was observed in patients who received prehospital tranexamic acid (odds ratio [OR], 1.34; 95% CI, 1.16-1.55; P < .001), compared with patients who did not receive prehospital tranexamic acid. After adjustment for confounders, no association between prehospital administration of tranexamic acid and mortality was found across the entire cohort of patients. However, a substantial increase in the odds of 30-day mortality persisted in patients with severe isolated TBI who received prehospital tranexamic acid (OR, 4.49; 95% CI, 1.57-12.87; P = .005) and after multiple imputations (OR, 2.05; 95% CI, 1.22-3.45; P = .007). 

Conclusions and relevance: This study found that prehospital tranexamic acid administration was associated with increased mortality in patients with isolated severe TBI, suggesting the judicious use of the drug when no evidence for extracranial hemorrhage is present.

 Early management of severe abdominal trauma 

Pierre Bouzat, Guillaume Valdenaire, Tobias Gauss, Jonhatan Charbit, Catherine Arvieux, Paul Balandraud, Xavier Bobbia, Jean-Stéphane David, Julien Frandon, Delphine Garrigue, Jean-Alexandre Long, Julien Pottecher, Bertrand Prunet, Bruno Simonnet, Karim Tazarourte, Christophe Trésallet, Julien Vaux, Damien Viglino, Barbara Villoing, Laurent Zieleskiewicz, Cédric Gil-Jardiné, Emmanuel Weiss

Anaesth Crit Care Pain Med 2020 Apr;39(2):269-277

Objective: To develop French guidelines on the management of patients with severe abdominal trauma.

Design: A consensus committee of 20 experts from the French Society of Anaesthesiology and Critical Care Medicine (Société française d'anesthésie et de réanimation, SFAR), the French Society of Emergency Medicine (Société française de médecine d'urgence, SFMU), the French Society of Urology (Société française d'urologie, SFU) and from the French Association of Surgery (Association française de chirurgie, AFC), the Val-de-Grâce School (École du Val-De- Grâce, EVG) and the Federation for Interventional Radiology (Fédération de radiologie interventionnelle, FRI-SFR) was convened. Declaration of all conflicts of interest (COI) policy by all participants was mandatory throughout the development of the guidelines. The entire guideline process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system for assessment of the available level of evidence with particular emphasis to avoid formulating strong recommendations in the absence of high level. Some recommendations were left ungraded.

Methods: The guidelines are divided in diagnostic and, therapeutic strategy and early surveillance. All questions were formulated according to Population, Intervention, Comparison, and Outcomes (PICO) format. The panel focused on three questions for diagnostic strategy: (1) What is the diagnostic performance of clinical signs to suggest abdominal injury in trauma patients? (2) Suspecting abdominal trauma, what is the diagnostic performance of prehospital FAST (Focused Abdominal Sonography for Trauma) to rule in abdominal injury and guide the prehospital triage of the patient? and (3) When suspecting abdominal trauma, does carrying out a contrast enhanced thoraco-abdominal CT scan allow identification of abdominal injuries and reduction of mortality? Four questions dealt with therapeutic strategy: (1) After severe abdominal trauma, does immediate laparotomy reduce morbidity and mortality? (2) Does a "damage control surgery" strategy decrease morbidity and mortality in patients with a severe abdominal trauma? (3) Does a laparoscopic approach in patients with abdominal trauma decrease mortality or morbidity? and (4) Does non-operative management of patients with abdominal trauma without bleeding reduce mortality and morbidity? Finally, one question was formulated regarding the early monitoring of these patients: In case of severe abdominal trauma, which kind of initial monitoring does allow to reduce the morbi-mortality? The analysis of the literature and the recommendations were conducted following the GRADE® methodology.

Results: The SFAR/SFMU Guideline panel provided 15 statements on early management of severe abdominal trauma. After three rounds of discussion and various amendments, a strong agreement was reached for 100% of recommendations. Of these recommendations, five have a high level of evidence (Grade 1±), six have a low level of evidence (Grade 2±) and four are expert judgments. Finally, no recommendation was provided for one question. 

Conclusions: Substantial agreement exists among experts regarding many strong recommendations for the best early management of severe abdominal trauma.

From battlefront to homefront: creation of a civilian walking blood bank

Maxwell A Braverman, Alison Smith, Charles Patrick Shahan, Benjamin Axtman, Eric Epley, Scott Hitchman, Elizabeth Waltman, Christopher Winckler, Susannah E Nicholson, Brian J Eastridge, Ronald M Stewart, Donald H Jenkins

Transfusion. 2020 Jun;60 Suppl 3:S167-S172 

Hemorrhagic shock remains the leading cause of preventable death on the battlefield, despite major advances in trauma care. Early initiation of balanced resuscitation has been shown to decrease mortality in the hemorrhaging patient. To address transfusion limitations in austere environments or in the event of multiple casualties, walking blood banks have been used in the combat setting with great success. Leveraging the success of the region-wide whole blood program in San Antonio, Texas, we report a novel plan that represents a model response to mass casualty incidents.

Outcomes following penetrating neck injury during the Iraq and Afghanistan conflicts: A comparison of treatment at US and United Kingdom medical treatment facilities

John Breeze, Douglas M Bowley, James G Combes, James Baden, Linda Orr, Andrew Beggs, Joseph DuBose, David B Powers

J Trauma Acute Care Surg 2020 May;88(5):696-703 

Abstract

Introduction: The United States and United Kingdom (UK) had differing approaches to the surgical skill mix within deployed medical treatment facilities (MTFs) in support of the military campaigns in Iraq and Afghanistan.

Methods: The US and UK combat trauma registries were scrutinized for patients with penetrating neck injury (PNI) at deployed coalition MTF between March 2003 and October 2011. A multivariate mixed effects logistic regression model (threshold, p < 0.05) was used stratified by MTF location and year of injury. The dependent variable was fatality on leaving Role 3, and the independent variables were ISS on arrival, nationality, MTF nationality, and presence of head and neck surgeon.

Results: A total of 3,357 (4.9%) of 67,586 patients who arrived alive at deployed military MTF were recorded to have sustained neck injuries; of which 2,186 (83%) were PNIs and the remainder were blunt injuries. When service members killed in action were included, the incidence of neck injury rose from 4.9% to 10%. Seven hundred nine (32%) of 2,186 patients with PNI underwent neck exploration; 555 patients were recorded to have sustained cervical vascular injury, 230 (41%) of 555 underwent vascular ligation or repair. Where it was recorded, PNI directly contributed to death in 64 (28%) of 228 of patients. Fatality status was positively associated with ISS on arrival (odds ratio, 1.05; 95% confidence interval, 1.04-1.06; p < 0.001) and the casualty being a local national (odds ratio, 1.74; 95% confidence interval, 1.28-2.38; p < 0.001).

Conclusion: Significant differences in the treatment and survival of casualties with PNI were identified between nations in this study; this may reflect differing cervical protection, management protocols, and surgical capability and is worthy of further study. In an era of increasing specialization within surgery, neck exploration remains a skill that must be retained by military surgeons deploying to Role 2 and Role 3 MTF.

Level of evidence: Retrospective cohort study, level III.

Combat Facial Fractures Sustained During Operation Resolute Support and Operation Freedom's Sentinel in Afghanistan 

John Breeze, William Gensheimer, Joseph J DuBose 

Mil Med. 2020 Sep 18;185(9-10):414-416 

Introduction: Facial fractures sustained in combat are generally unrepresentative of those commonly experienced in civilian practice. In the US military, acute trauma patient care is guided by the Joint Trauma System Clinical Practice Guidelines but currently none exists for facial trauma. 

Materials and methods: All casualties that underwent surgery to facial fractures between January 01, 2016 and September 15, 2019 at a US deployed Military Treatment Facility in Afghanistan were identified using the operating room database. Surgical operative records and outpatient records for local Afghan nationals returning for follow-up were reviewed to determine outcomes. 

Results: 55 casualties underwent treatment of facial fractures; these were predominantly from explosive devices (27/55, 49%). About 46/55 (84%) were local nationals, of which 32 (70%) were followed up. Length of follow-up ranged between 1 and 25 months. About 36/93 (39%) of all planned procedures developed complications, with the highest being from ORIF mandible (18/23, 78%). About 8/23 (35%) casualties undergoing ORIF mandible developed osteomyelitis, of which 5 developed nonunion. Complications were equally likely to occur in those procedures for "battlefield type" events such as explosive devices and gunshot wounds (31/68, 46%) as those from "civilian type" events such as falls or motor vehicle collisions (5/11, 45%). 

Conclusions: Complications Rates from facial fractures were higher than that reported in civilian trauma. This likely reflects factors such as energy deposition, bacterial load, and time to treatment. Load sharing osteosynthesis should be the default modality for fracture fixation. External fixation should be considered in particular for complex high-energy or infected mandible fractures where follow-up is possible.

One Notable Complication of Nasopharyngeal Airway: A Case Report 

Blake Briggs, Chase Countryman, Henderson D McGinnis 

Clin Pract Cases Emerg Med. 2020 Nov;4(4):584-586 

Introduction: The nasopharyngeal airway (NPA) is used by emergency providers and first responders to assist with oxygenation in obtunded, critically ill patients. There are few recorded NPA complications. 

Case report: We describe a unique case in which a patient went multiple days with recurrent symptoms of upper airway obstruction secondary to retained NPA. 

Discussion: Nasopharyngeal airways may be uniquely prone to being displaced and retained due to their use in emergent situations, their small size, and time of insertion in the field prior to emergency department (ED) contact where handoff is not often standardized. 

Conclusion: The use of large-flanged NPAs might reduce incidences of displacement into the nasal cavity. This case highlights the need for improved handoff communication between emergency medical services and ED staff, especially to account for all inserted devices to prevent foreign body retention.

Early tranexamic acid in traumatic brain injury: Evidence for an effective therapy Nuray Sarmad Bukhari, Rashid Jooma

J Pak Med Assoc 2020 Feb;70(Suppl 1)(2):S49-S52. 

Abstract

The guidelines for management of traumatic brain injury (TBI) are based largely on measures to maintain an optimum internal milieu for prevention of secondary brain injury and enhancing recovery. One of the most common reasons for worsening outcomes following TBI is expanding intracranial haematoma which is compounded by the fibrinolytic physiology that follows TBI. Tranexamic acid (TXA) has a time tested role in preventing poor outcomes linked to excessive haemorrhage in trauma patients. Historically, patients with isolated head trauma were excluded from TXA use due to a theoretical increased risk of thrombosis. Recent evidence that redefines the beneficial role of early TXA administration in preventing mortality amongst patients with TBI is now at hand and offers a real prospect of a pharmacological intervention that would be adopted as a recommendation based on Class l evidence.

Evaluation of a novel handheld point-of-care ultrasound device in an African emergency department 

Samuel L Burleson, Jonathan F Swanson, Erin F Shufflebarger, Douglas W Wallace, Matthew A Heimann, James C Crosby, David C Pigott, John P Gullett, Maxwell A Thompson, Christopher J Greene 

Ultrasound J. 2020 Dec 7;12(1):53 

Background: Many point-of-care ultrasound devices are now "pocket-sized" or handheld, allowing easy transport during travel and facilitating use in crowded spaces or in austere low-resource settings. Concerns remain about their durability, image quality, and clinical utility in those environments. 

Method: Five emergency physicians with training in point-of-care ultrasound employed the Butterfly iQ, a novel handheld ultrasound device, in routine clinical care in a busy, high-acuity African emergency department over a period of 10 weeks. We retrospectively evaluated the performance of the Butterfly iQ from the perspectives of both the clinicians using the device and expert ultrasound faculty reviewing the images. 

Results: We found advantages of the Butterfly iQ in a high-acuity African emergency department include its use of a single probe for multiple functions, small size, ease of transport, relatively low cost, and good image quality in most functions. Disadvantages include large probe footprint, lower, though still adequate, cardiac imaging quality, frequent overheating, and reliance on internet-based cloud storage, but these were surmountable. We also report a wide variety of patient presentations, pathology, and procedures to which the device was used. 

Conclusion: We conclude the Butterfly iQ is an effective, though imperfect, point-of-care ultrasound device in a low-resource emergency setting. We will continue to employ the device in clinical emergency care and teaching in this setting.

Resuscitative Endovascular Balloon Occlusion of the Aorta Process Improvement: Examining a Novel Case Evaluation Tool and Standardized Simulations 

David J Burkard, Jessica Thompson, Matthew Dull, Jennifer Haverkamp, Amy Koestner, Alan Davis, Cathryn Chadwick, Charles J Gibson, Gaby Iskander, Alistair J Chapman

Trauma Nurs Mar/Apr 2020;27(2):82-87 

A quality improvement project was undertaken. The objectives of this study were to describe an original case evaluation tool, discuss barriers encountered, present a standardized simulation course, and evaluate the efficacy of this course. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging adjunct in the trauma bay for patients with noncompressible subdiaphragmatic hemorrhage. Compared with the alternative (emergency department thoracotomy), it is less invasive and allows for continuation of chest compressions, and early studies suggest a positive effect on mortality. Infrequent utilization of REBOA limits provider and support staff exposure to its indications and technical skills required to deploy the device. Furthermore, there is no standardized evaluation tool for collecting and reporting REBOA-related data. The REBOA Review Tool was designed to easily evaluate all the steps involved in deploying the REBOA tool and was implemented at our institution without difficulty. This tool provided meaningful feedback for areas that required improvement including ease of information retrieval and documentation of sheath removal. Standardized simulation courses were performed to further improve provider and support staff confidence in using the REBOA tool. Analysis of pre- and postsimulation surveys showed significant improvement in participants' confidence in their understanding and utilization of the REBOA tool and its indications. REBOA placement is a low-volume but high-impact procedure. Therefore, simulations to prepare and a standardized tool to learn from prior experience are vital to improving patient care.

CE: Trauma-Related Hemorrhagic Shock: A Clinical Review 

Nicole W Caldwell, Mithun Suresh, Tricia Garcia-Choudary, Christopher A VanFosson 

Am J Nurs. 2020 Sep;120(9):36-43 

Abstract 

Optimal management of trauma-related hemorrhagic shock begins at the point of injury and continues throughout all hospital settings. Several procedures developed on the battlefield to treat this condition have been adopted by civilian health care systems and are now used in a number of nonmilitary hospitals. Despite the important role nurses play in caring for patients with trauma-related hemorrhagic shock, much of the literature on this condition is directed toward paramedics and physicians. This article discusses the general principles underlying the pathophysiology and clinical management of trauma-related hemorrhagic shock and updates readers on nursing practices used in its management.

Effectiveness of different supralottic airways during resuscitation manoeuvres. A systematic review

J Calheiros, P Charco-Mora

Rev Esp Anestesiol Reanim Jun-Jul 2020;67(6):316-324 

Introduction: Supraglottic airways, which are easily inserted and minimize interruptions in cardiopulmonary resuscitation manoeuvres, are now widely used in pre- and in-hospital emergencies. However, most studies in these devices do not specify whether they ensure good ventilation during CPR. This systematic review aims to determine whether there is evidence that supraglotic airways enable effective ventilation during resuscitation.

Methods: The MEDLINE and COCHRANE databases were searched for studies published in English up to 30 November 2018. Eligible studies were all those that objectively evaluated tidal volume during resuscitation maneuvers in patients over 18 years of age using various supraglottic airways.

Results: A total of 3734 articles were identified, of which 252 were duplicates. Only 1 objectively evaluated ventilation during resuscitation maneuvers and presented data relevant to this review. The study included 470 patients, 51 of which underwent spirometry. Only 4.48% of patients survived to hospital discharge; however, the correlation with ventilation effectiveness was not assessed.

Conclusion: There is no scientific evidence that supraglottic airways provide effective ventilation during resuscitation maneuvers. Evaluation by spirometry, chest impedance and ultrasound may help to determine the ventilatory efficacy of supraglottic airways during CPR, and clarify whether this factor contributes to the difficulties experienced in reversing cardiorespiratory arrest.

Topical Antimicrobial Agents for Burn Wound Care: History and Current Status 

Leopoldo C Cancio 

Surg Infect (Larchmt). 2021 Feb;22(1):3-11. 

Background: Infection is the leading cause of death after thermal injury. Optimal prevention and treatment of burn wound infection is enabled by an in-depth understanding of burn wound treatment modalities not only from a technical standpoint, but also from the standpoint of the clinical context in which these modalities were originally developed. Methods: A review of the historical literature on the topical antimicrobial care of burn wounds was performed. Results: As our understanding of post-burn infection evolved, and as new products were developed for the prevention of post-burn wound infection, major advances in post-burn survival occurred. Ultimately, improvements in anesthetic, surgical, and critical care management have permitted early excision and grafting of the burn wound, decreasing but not eliminating the importance of topical antimicrobial care, and shifting much of the burden of wound infection prevention to the post-operative period. Conclusions: The development of effective topical antimicrobial agents for wound care was, arguably, the single most important advance in the care of the burn patient. Still, many gaps in our ability to treat complicated burn wounds remain. Fungal infection is an unusual but daunting challenge. Patients with impaired wound healing and those with advanced age or medical comorbidities may not benefit from early excision, and the benefits of early excision may not be available in austere or remote locations. For these reasons, research on optimal topical treatment continues.

Comprehensive analysis of combat casualty outcomes in U.S. servicemembers from the beginning of World War II to the end of Operation Enduring Freedom

Jeremy W Cannon, Daniel N Holena, Zhi Geng, Ian J Stewart, Yanlan Huang, Wei Yang, Emily R Mayhew, Shawn C Nessen, Kirby R Gross, C William Schwab 

J Trauma Acute Care Surg. 2020 Aug;89(2S Suppl 2):S8-S15 

Advances in combat casualty care have improved combat survivability over the past two decades. However, these outcomes remain incompletely framed in the broader context of combat casualty outcomes over the past eighty years. We hypothesized that starting with World War II, combat survival worsened at the beginning of each new conflict but then improved over time. To evaluate long-term trends in combat casualty outcomes, monthly combat injuries and deaths during World War II, the Korean conflict, the Vietnam conflict, Operation Iraqi Freedom (OIF), and Operation Enduring Freedom (OEF) were collated. From these numbers, we calculated the monthly case fatality rate (CFR), the killed in action rate (%KIA), and the died of wounds rate (%DOW). We analyzed these metrics for significant trends during and between each conflict using linear and Loess regression. We then simulated alternate outcome scenarios by eliminating outcome variability. In this comprehensive analysis, CFR decreased over the study period in parallel with a decrease in %KIA. When examining individual conflicts, however, several unfavorable trends emerged including a spike in all fatality measures at the end of Vietnam and a rise in %DOW over the course of Korea and OIF. In comparing CFR at the beginning of each conflict to the best CFR from the prior conflict, high mortality outliers occurred in every conflict after a period of relative peace, and a clear "peacetime effect" occurred in both World War II and Vietnam. Eliminating these negative trends and the attendant preventable deaths would have reduced combat fatalities over the course of eighty years by 107,256 (39.7%). In summary, although combat mortality rates have generally improved since World War II, closer examination indicates several unfavorable trends both during and between conflicts. Identifying factors behind these trends will reveal further opportunities to improve combat casualty outcomes in the future.

LEVEL OF EVIDENCE: III, Epidemiological.

An analysis of US Africa command area of operations military medical transportations, 2008-2018

Brandon Carius, William T Davis, Carlissa D Linscomb, Mireya A Escandon, Dylan Rodriguez, Nguvan Uhaa, Joseph K Maddry, Kevin K Chung, Steve Schauer

Afr J Emerg Med 2020 Mar;10(1):13-16 

Introduction: With personnel scattered throughout a continent 3 times larger than the United States, a lack of mature medical facilities necessitates a significant transportation network for medical evacuation in US Africa Command (AFRICOM). We describe medical evacuations analyzed from the US Air Force Transportation Command Regulating and Command & Control Evacuation System (TRAC2ES).

Methods: We performed a retrospective review of all TRAC2ES medical records for medical evacuations from the AFRICOM theater of operations conducted between January 1, 2008 and December 31, 2018. We abstracted free text data entry in TRAC2ES for diagnostic and therapeutic interventions performed prior to the patient movement request.

Results: During this time, there were 963 cases recorded in TRAC2ES originating within AFRICOM. 961 records were complete for analysis. Most patients were male (82%) and military personnel (92%). Most transports originated in Djibouti (72%), and Germany (93%) was the most common destination. Medical evacuations were largely routine (66%), and routine evacuations were proportionally highest amongst US military personnel compared to all other groups. A small portion of patients were evacuated for battle injuries (4%), compared to non- battle injury (33%) and disease (63%). Within disease, the largest proportion of patient complaints centered on gastrointestinal symptoms (13%), behavioral health (11%) and chest pain (8%). Prior to evacuation, only 55% of patients were document as receiving any medication. Pain control was documented in 21% of cases, most commonly being NSAIDs (7%).

Discussion: Extremely low numbers of battle injuries highlight the unique nature of AFRICOM operations compared to areas with more intense combat operations. Limitations of the dataset highlight the need for a data collection mandate within AFRICOM as within other areas for optimization and performance improvement.

A Response to "A Comparison of Improvised and Commercially Available Point-of-Wounding Tourniquets in Simulated Traumatic Amputation with Catastrophic Hemorrhage"

Brandon M Carius, Peter M Dodge, Andrew D Fisher

Mil Med. 2020 Oct 2;usaa262. doi: 10.1093/milmed/usaa262

No abstract available

An Analysis of Exertional Safety After Blood Donation in Active Duty Military Personnel-A Feasibility Study

Brandon M Carius, Mohamad Umar, James K Aden, Steve G Schauer

Mil Med. 2020 Nov 2;usaa234 Online ahead of print 

Introduction: Whole blood (WB) is the optimal resuscitation fluid in hemorrhagic shock. Military research focuses on mortality benefits of WB acquired through walking blood banks (WBBs). Few military-based studies on donation effects exist, almost exclusively performed on small special operation forces. No Department of Defense regulations for postdonation precautions in nonaviation crew members exist. Further study is warranted regarding safety and limitations in postdonation populations.

Materials and methods: A feasibility (n = 25) prospective interventional study examined the safety of exertion (defined as a 1.6-km treadmill run at volunteers' minimum passing pace for the Army Physical Fitness Test) following 1 unit of WB donation. Subjects served as their own controls, performing baseline testing 7 days before donation, with repeat testing 1 h following donation conducted by Armed Services Blood Program personnel. Adverse events, pre- and postexertion vital signs (VS) were evaluated.

Results: There were no adverse events throughout testing. Only resting heart rate (68 vs. 73 beats · min-1, p < 0.01) and postexertion heart rate were significantly different among pre- and postdonation VS. Additional significant findings were time to attain postexertion normocardia (116 vs. 147 seconds, p < 0.01). A small but statistically significant change in Borg perceived exertional scores was noted (10.3 vs. 10.8, p < 0.05).

Conclusions: This feasibility study demonstrates the first safety test of regular military populations performing exertion immediately following the standardized WB donation. VS changes may translate into a small but significant increase in perceived postdonation exertion. Future studies should expand duration and intensity of exertion to match combat conditions.

Battlefield Vital Sign Monitoring in Role 1 Military Treatment Facilities: A Thematic Analysis of After-Action Reviews from the Prehospital Trauma Registry

Brandon M Carius, Jason F Naylor, Michael D April, Andrew D Fisher, Ian L Hudson, Peter J Stednick, Joseph K Maddry, Erik K Weitzel, Victor A Convertino, Steve G Schauer

Mil Med. 2020 Nov 26;usaa515. doi: 10.1093/milmed/usaa515. Online ahead of print. 

Introduction: The Prehospital Trauma Registry (PHTR) captures after-action reviews (AARs) as part of a continuous performance improvement cycle and to provide commanders real-time feedback of Role 1 care. We have previously described overall challenges noted within the AARs. We now performed a focused assessment of challenges with regard to hemodynamic monitoring to improve casualty monitoring systems.

Materials and methods: We performed a review of AARs within the PHTR in Afghanistan from January 2013 to September 2014 as previously described. In this analysis, we focus on AARs specific to challenges with hemodynamic monitoring of combat casualties.

Results: Of the 705 PHTR casualties, 592 had available AAR data; 86 of those described challenges with hemodynamic monitoring. Most were identified as male (97%) and having sustained battle injuries (93%), typically from an explosion (48%). Most were urgent evacuation status (85%) and had a medical officer in their chain of care (65%). The most common vital sign mentioned in AAR comments was blood pressure (62%), and nearly one-quarter of comments stated that arterial palpation was used in place of blood pressure cuff measurements.

Conclusions: Our qualitative methods study highlights the challenges with obtaining vital signs-both training and equipment. We also highlight the challenges regarding ongoing monitoring to prevent hemodynamic collapse in severely injured casualties. The U.S. military needs to develop better methods for casualty monitoring for the subset of casualties that are critically injured.

In response to Early and prehospital trauma deaths: emergency physicians should not be alone to win the game

Shannon L Carroll, John B Holcomb, Jan O Jansen

J Trauma Acute Care Surg 2020 May 26; Online ahead of print. 

No abstract available

Civilian prehospital transfusion - experiences from a French region 

Arnaud Cassignol, Julien Marmin, Pascal Mattei, Léa Goffinet, Sandrine Pons, Aurélien Renard, Didier Demory, Julien Bordes 

Vox Sang. 2020 Nov;115(8):745-755 

Background and objectives: Haemorrhagic shock is a leading cause of avoidable mortality in prehospital care. For several years, our centre has followed a procedure of transfusing two units of packed red blood cells outside the hospital. Our study's aim was twofold: describe the patient characteristics of those receiving prehospital blood transfusions and analyse risk factors for the 7-day mortality rate. 

Materials and methods: We performed a monocentric retrospective observational study. Demographic and physiological data were recovered from medical records. The primary outcome was mortality at seven days for all causes. All patients receiving prehospital blood transfusions between 2013 and 2018 were included. 

Results: Out of 116 eligible patients, 56 patients received transfusions. Trauma patients (n = 18) were younger than medical patients (n = 38) (P = 0·012), had lower systolic blood pressure (P = 0·001) and had higher haemoglobin levels (P = 0·016). Mortality was higher in the trauma group than the medical group (P = 0·015). In-hospital trauma patients received more fresh-frozen plasma and platelet concentrate than medical patients (P < 0·05). Predictive factors of 7-day mortality included transfusion for trauma-related reasons, low Glasgow Coma Scale, low peripheral oxygen saturation, prehospital intensive resuscitation, existing coagulation disorders, acidosis and hyperlactataemia (P < 0·05). 

Conclusion: Current guidelines recommend early transfusion in patients with haemorrhagic shock. Prehospital blood transfusions are safe. Coagulation disorders and acidosis remain a cause of premature death in patients with prehospital transfusions.

Civilian prehospital transfusion - experiences from a French region 

Arnaud Cassignol, Julien Marmin, Pascal Mattei, Léa Goffinet, Sandrine Pons, Aurélien Renard, Didier Demory, Julien Bordes 

Vox Sang. 2020 Nov;115(8):745-755 

Background and objectives: Haemorrhagic shock is a leading cause of avoidable mortality in prehospital care. For several years, our centre has followed a procedure of transfusing two units of packed red blood cells outside the hospital. Our study's aim was twofold: describe the patient characteristics of those receiving prehospital blood transfusions and analyse risk factors for the 7-day mortality rate. 

Materials and methods: We performed a monocentric retrospective observational study. Demographic and physiological data were recovered from medical records. The primary outcome was mortality at seven days for all causes. All patients receiving prehospital blood transfusions between 2013 and 2018 were included. 

Results: Out of 116 eligible patients, 56 patients received transfusions. Trauma patients (n = 18) were younger than medical patients (n = 38) (P = 0·012), had lower systolic blood pressure (P = 0·001) and had higher haemoglobin levels (P = 0·016). Mortality was higher in the trauma group than the medical group (P = 0·015). In-hospital trauma patients received more fresh-frozen plasma and platelet concentrate than medical patients (P < 0·05). Predictive factors of 7-day mortality included transfusion for trauma-related reasons, low Glasgow Coma Scale, low peripheral oxygen saturation, prehospital intensive resuscitation, existing coagulation disorders, acidosis and hyperlactataemia (P < 0·05). 

Conclusion: Current guidelines recommend early transfusion in patients with haemorrhagic shock. Prehospital blood transfusions are safe. Coagulation disorders and acidosis remain a cause of premature death in patients with prehospital transfusions.

Early and prehospital trauma deaths: emergency physicians should not be alone to win the game 

Nicolas Cazes, Aurélien Renard, Daniel Meyran

Trauma Acute Care Surg 2020 May 26;Online ahead of print 

No abstract available

Conversion of I-gel to definitive airway in a cervical immobilized manikin: Aintree intubation catheter vs long endotracheal tube 

Yun Jeong Chae, Heirim Lee, Bokyeong Jun, In Kyong Yi 

BMC Anesthesiol. 2020 Jun 18;20(1):152 

Background: After prehospital insertion of i-gel, a popular supraglottic airway (SGA), fiberoptic-guided intubation through i-gel is often required to switch the i-gel to a definitive airway for anticipated difficult airway. The Aintree intubation catheter (AIC) was developed for this purpose yet it requires many procedural steps during which maintenance of adequate ventilation is difficult. We custom-made a long endotracheal tube (LET) which may facilitate this procedure and compared the efficacy of the AIC and LET in a cervical immobilized manikin. 

Methods: In this 2 × 2 crossover manikin-based trial, 20 anaesthesiologists and residents performed both methods in random order. Total intubation time, fiberoptic time, and procedure time were recorded. The ease of insertion, procedure failure rate, difficulty score, and participants' preference were recorded. 

Results: Total intubation time was significantly shorter for the LET than the AIC group (70.8 ± 16.4 s vs 94.0 ± 28.4 s, P = 0.001). The procedure time was significantly shorter in the LET group (51.9 ± 13.8 s vs 76.5 ± 25.4 s, P < 0.001). The ease of insertion score was lower, i.e., easier, in the AIC than the LET group (2.0 [1.0-2.75] vs 1.0 [1.0-1.0], P < 0.001). Fiberoptic time (19.0 ± 6.9 s vs 17.5 ± 12.3 s) and subjective difficulty (4.0 [3.0-6.0] vs 4.0 [3.0-5.75]) were similar between groups. Fourteen participants preferred the LET method (70%) due to its fewer procedural steps. 

Conclusions: LET resulted in a shorter intubation time than the AIC during fiberoptic-guided intubation through the i-gel, possibly due to the less procedural steps compared to AIC.

Head Rotation Reduces Oropharyngeal Leak Pressure of the i-gel and LMA® Supreme™ in Paralyzed, Anesthetized Patients: A Randomized Trial 

Tomohiro Chaki, Shunsuke Tachibana, Sho Kumita, Honami Sato, Kosuke Hamada, Yasuyuki Tokinaga, Michiaki Yamakage 

Anesth Analg. 2021 Mar 1;132(3):818-826. 

Background: Second-generation supraglottic airway (SGA) devices are useful for airway management during positive pressure ventilation in general anesthesia and emergency medicine. In some clinical settings, such as the anesthetic management of awake craniotomy, SGAs are used in the head-rotated position, which is required for exposure of the surgical field, although this position sometimes worsens the efficiency of mechanical ventilation with SGAs. In this study, we investigated and compared the influence of head rotation on oropharyngeal leak pressures (OPLP) of the i-gel and LMA® Supreme™, which are second-generation SGA devices. 

Methods: Patients who underwent elective surgery under general anesthesia were enrolled in this study and randomly divided into i-gel or LMA Supreme groups. After induction of anesthesia with muscle relaxation, the i-gel or LMA Supreme was inserted according to computerized randomization. The primary outcome was the OPLP at 0°, 30°, and 60° head rotation. The secondary outcomes were the maximum airway pressure and expiratory tidal volume when patients were mechanically ventilated using a volume-controlled ventilation mode with a tidal volume of 10 mL/kg (ideal body weight), ventilation score, and fiber-optic views of vocal cords. 

Results: Thirty-four and 36 participants were included in the i-gel and LMA Supreme groups, respectively. The OPLPs of the i-gel and LMA Supreme significantly decreased as the head rotation angle increased (mean difference [95% confidence interval], P value: i-gel; 0° vs 30°: 3.5 [2.2-4.8], P < .001; 30° vs 60°: 2.0 [0.6-3.5], P = .002; 0° vs 60°: 5.5 [3.3-7.8], P < .001, LMA Supreme; 0° vs 30°: 4.1 [2.6-5.5], P < .001; 30° vs 60°: 2.4 [1.1-3.7], P < .001; 0° vs 60°: 6.5 [5.1-8.0], P < .001). There were statistically significant differences in expiratory tidal volume and ventilation score between 0° and 60° in the i-gel group and in ventilation score between 30° and 60° in the LMA Supreme group. There was no statistically significant difference between the 2 devices in all outcome measures. The incidences of adverse events, such as hoarseness or sore throat, were not significantly different between i-gel and LMA Supreme. 

Conclusions: Head rotation to 30° and 60° reduces OPLP with both i-gel and LMA Supreme. There is no difference in OPLP between i-gel and LMA Supreme in the 3 head rotation positions.

Telehealth Impact on Primary Care Related Ambulance Transports

Tiffany Champagne-Langabeer, James R Langabeer, Kirk E Roberts, Joshua S Gross, Guy R Gleisberg, Michael G Gonzalez, David Persse

Prehosp Emerg Care Sep-Oct 2019;23(5):712-717 

Introduction: Telehealth has been used nominally for trauma, neurological, and cardiovascular incidents in prehospital emergency medical services (EMS). Yet, much less is known about the use of telehealth for low-acuity primary care. We examine the development of one telehealth program and its impact on unnecessary ambulance transports.

Objective: The objective of this study is to describe the development and impact of a large- scale telehealth program on ambulance transports.

Methods: We describe the patient characteristics and results from a cohort of patients in Houston, Texas who received a prehospital telehealth consultation from an emergency medicine physician. Inclusion criteria were adults and pediatric patients with complaints considered to be non-urgent, primary care related. Data were analyzed for 36 months, from January 2015 through December 2017. Our primary dependent variable was the percentage of patients transported by ambulance. We used descriptive statistics to describe patient demographics, chi-square to examine differences between groups, and logistic regression to explore the effects with multivariate controls including age, gender, race, and chief complaint.

Results: A total of 15,067 patients were enrolled (53% female; average age 44 years ± 19 years) over the three-year period. The 3 primary chief complaints were based on abdominal pains (13% of cases), nausea/vomiting/diarrhea (NVD) (9.4%), and back pain (9.3%).

Ambulance transports represented 11.2% of all transports in the program, while alternative taxi transportation was used in 75.6%, and the remainder were self- or no-transports. Taxi transportation to an alternate, affiliated clinic (versus ED) was utilized in 5% of incidents. After multivariate controls, older age patients presenting with low-risk, non-acute chest pain, shortness of breath, and dizziness were much more likely to use ambulance transport. Race and gender were not significant predictors of ambulance transport.

Conclusions: We found telehealth offers a technology strategy to address potentially unnecessary ambulance transports. Based on prior cost-effectiveness analyses, the reduction of unnecessary ambulance transports translates to an overall reduction in EMS agency costs. Telehealth programs offer a viable solution to support alternate destination and alternate transport programs.

Clinical evaluation of the use of laryngeal tube verses laryngeal mask airway for out-of-hospital cardiac arrest by paramedics in Singapore

Jing Jing Chan, Zi Xin Goh, Zhi Xiong Koh, Janice Jie Er Soo, Jes Fergus, Yih Yng Ng, John Carson Allen Jr, Marcus Eng Hock Ong

Singapore Med J. 2020 Aug 17. doi: 10.11622/smedj.2020119. Online ahead of print. 

Introduction: It is unclear which advanced airway device has better placement success and fewer adverse events in out-of-hospital cardiac arrests (OHCAs). This study aimed to evaluate the efficacy of the VBM laryngeal tube (LT) against the laryngeal mask airway (LMA) in OHCAs managed by emergency ambulances in Singapore.

Methods: This was a real-world, prospective, cluster-randomised crossover study. All OHCA patients above 13 years old who were suitable for resuscitation were randomised to receive either LT or LMA. The primary outcome was placement success. Per-protocol analysis was performed and association between outcomes and airway device group was compared using multivariate binomial logistic regression analysis.

Results: Of 965 patients with OHCAs from March 2016 to January 2018, 905 met the inclusion criteria, of which 502 (55.5%) were randomised to receive LT while 403 (44.5%) were randomised to receive LMA. Only 174 patients in the LT group actually received the device due to noncompliance. Placement success for LT was lower than for LMA (adjusted odds ratio [OR] 0.52, 95% confidence interval [CI] 0.31-0.90). Complications were more likely when using LT (OR 2.82,0 95% CI 1.64-4.86). Adjusted OR for prehospital return of spontaneous circulation (ROSC) was similar in both groups. A modified intention-to-treat analysis showed similar outcomes to the per-protocol analysis between the groups.

Conclusion: LT was associated with poorer placement success and higher complication rates than LMA. The likelihood of prehospital ROSC was similar between the two groups. Familiarity bias and a low compliance rate to the LT were the main limitations of this study.

The adhesion of clots in wounds contributes to hemostasis and can be enhanced by coagulation factor XIII

Karen Y T Chan, Alyssa S M Yong, Xu Wang, Kristyn M Ringgold, Alexander E St John, James R Baylis, Nathan J White, Christian J Kastrup

Sci Rep. 2020 Nov 18;10(1):20116. doi: 10.1038/s41598-020-76782-z. 

Abstract

The adhesion of blood clots to wounds is necessary to seal injured vasculature and achieve hemostasis. However, it has not been specifically tested if adhesive failure of clots is a major contributor to rebleeding and what mechanisms prevent clot delamination. Here, we quantified the contribution of adhesive and cohesive failure to rebleeding in a rat model of femoral artery injury, and identified mechanisms that contribute to the adhesive strength of bulk clots in a lap-shear test in vitro. In the rat bleeding model, the frequency of clot failures correlated positively with blood loss (R = 0.81, p = 0.014) and negatively with survival time (R = - 0.89, p = 0.0030), with adhesive failures accounting for 51 ± 14% of rebleeds. In vitro, adhesion depended on fibrinogen and coagulation factor XIII (FXIII), and supraphysiological FXIII improved adhesive strength. Furthermore, when exogenous FXIII was topically applied into the wound pocket of rats, eleven adhesive failures occurred between eight rats, compared to seventeen adhesive failures between eight untreated rats, whereas the number of cohesive failures remained the same at sixteen in both groups. In conclusion, rebleeding from both adhesive and cohesive failure of clots decreases survival from hemorrhage in vivo. Both endogenous and exogenous FXIII improves the adhesive strength of clots.

Hindfoot blast injuries caused by improvised explosive devices: long-term functional assessment in French military personnel

Anaïs Chataigneau, Alexia Milaire, Paul-Vincent Martin, Julien Danis, Fabrice Bazile, Nicolas de l'Escalopier, Laurent Mathieu

Int Orthop. 2021 Mar;45(3):751-757 

Purpose: The chosen treatment and long-term evaluation of hindfoot blast injuries are not well-represented in the literature. The first objective of this retrospective study was to evaluate functional outcomes in French service personnel who had sustained such injuries caused by improvised explosive devices. The second objective was to compare the results for patients who had amputations with those who did not. The hypothesis was that amputee recovered better function.

Methods: Long-term functional evaluations were carried out using the American Orthopaedic Foot and Ankle Society scale (AOFAS), the Foot and Ankle Ability Measure (FAAM), and the Short Form 12 health survey (SF-12).

Results: Eight servicemen with ten hindfoot blast injuries were reviewed at a mean follow-up time of seven years. Primary management was always conservative although half of the patients required late amputation for chronic pain. The patients who underwent amputation reported significantly lower levels of pain than those who did not have an amputation, with higher FAAM and SF-12 scores.

Conclusion: In this series, long-term functional results appear better in the amputated group.

Physiological response to fluid resuscitation with Ringer lactate versus Plasmalyte in critically ill burn patients

Maïté Chaussard, François Dépret, Oriane Saint-Aubin, Mourad Benyamina, Maxime Coutrot, Marion Jully, Haikel Oueslati, Alexandre Fratani, Alexandru Cupaciu, Alicia Poniard, Karim Asehnoune, Solohaja-Faniaha Dimby, Alexandre Mebazaa, Pascal Houze, Matthieu Legrand

J Appl Physiol (1985) 2020 Mar 1;128(3):709-714 

Abstract 

The metabolic consequences in vivo of various balanced solutions are poorly known in critically ill patients. The main objective of this study was to describe the metabolic consequences of Plasmalyte versus Ringer lactate (RL) in critically ill burn patients, with a special focus on the plasma clearance of buffer anions (i.e., gluconate, acetate, and lactate). We conducted a randomized trial between August 2017 and October 2018 in a tertiary teaching hospital in Paris, France. Patients with burn total body surface area >30% were randomized to receive Plasmalyte or RL. The primary end point was the base excess 24 h after inclusion. The secondary end points were acetate, gluconate, and lactate plasma concentration, the strong ion difference (SID). Twenty-eight patients were randomized. Twenty-four hours after inclusion, plasma BE was not significantly different in the Plasmalyte and RL groups {-0.9 [95% confidence interval (95% CI): -1.8-0.9] vs. -2.1 [95% CI: -4.6-0.6] mmol/L, respectively, P = 0.26}. Plasma gluconate concentration was higher in the Plasmalyte group (P < 0.001), with a maximum level of 1.86 (95% CI: 0.98-4.0) mmol/L versus 0 (95% CI: 0-0.15) mmol/L. Plasma acetate and lactate were not significantly different. Ionized calcium level was lower in the Plasmalyte group (P = 0.002). Hemodynamics did not differ between groups. To conclude, the alkalinizing effect of Plasmalyte was less important than expected with no difference in base excess compared with RL, in part due to gluconate accumulation. Acetate and lactate did not significantly accumulate. Plasmalyte led to significantly lower ionized calcium levels.NEW & NOTEWORTHY During fluid resuscitation in burns the alkalinizing effect of Plasmalyte was less important than expected, with no difference in base excess compared with Ringer lactate (RL), in part due to gluconate accumulation. Acetate and lactate did not significantly accumulate.

 

Plasmalyte led to significantly lower ionized calcium levels.

Association between prehospital time and outcome of trauma patients in 4 Asian countries: A cross-national, multicenter cohort study 

Chi-Hsin Chen, Sang Do Shin, Jen-Tang Sun, Sabariah Faizah Jamaluddin, Hideharu Tanaka, Kyoung Jun Song, Kentaro Kajino, Akio Kimura, Edward Pei-Chuan Huang, Ming-Ju Hsieh, Matthew Huei-Ming Ma, Wen-Chu Chiang 

PLoS Med. 2020 Oct 6;17(10):e1003360 

Background: Whether rapid transportation can benefit patients with trauma remains controversial. We determined the association between prehospital time and outcome to explore the concept of the "golden hour" for injured patients. 

Methods and findings: We conducted a retrospective cohort study of trauma patients transported from the scene to hospitals by emergency medical service (EMS) from January 1, 2016, to November 30, 2018, using data from the Pan-Asia Trauma Outcomes Study (PATOS) database. Prehospital time intervals were categorized into response time (RT), scene to hospital time (SH), and total prehospital time (TPT). The outcomes were 30-day mortality and functional status at hospital discharge. Multivariable logistic regression was used to investigate the association of prehospital time and outcomes to adjust for factors including age, sex, mechanism and type of injury, Injury Severity Score (ISS), Revised Trauma Score (RTS), and prehospital interventions. Overall, 24,365 patients from 4 countries (645 patients from Japan, 16,476 patients from Korea, 5,358 patients from Malaysia, and 1,886 patients from Taiwan) were included in the analysis. Among included patients, the median age was 45 years (lower quartile [Q1]-upper quartile [Q3]: 25-62), and 15,498 (63.6%) patients were male. Median (Q1-Q3) RT, SH, and TPT were 20 (Q1-Q3: 12-39), 21 (Q1-Q3: 16-29), and 47 (Q1-Q3: 32-60) minutes, respectively. In all, 280 patients (1.1%) died within 30 days after injury. Prehospital time intervals were not associated with 30-day mortality. The adjusted odds ratios (aORs) per 10 minutes of RT, SH, and TPT were 0.99 (95% CI 0.92-1.06, p = 0.740), 1.08 (95% CI 1.00-1.17, p = 0.065), and 1.03 (95% CI 0.98-1.09, p = 0.236), respectively. However, long prehospital time was detrimental to functional survival. The aORs of RT, SH, and TPT per 10-minute delay were 1.06 (95% CI 1.04-1.08, p < 0.001), 1.05 (95% CI 1.01-1.08, p = 0.007), and 1.06 (95% CI 1.04-1.08, p < 0.001), respectively. The key limitation of our study is the missing data inherent to the retrospective design. Another major limitation is the aggregate nature of the data from different countries and unaccounted confounders such as in-hospital management.

Association between prehospital time and outcome of trauma patients in 4 Asian countries: A cross-national, multicenter cohort study 

Chi-Hsin Chen, Sang Do Shin, Jen-Tang Sun, Sabariah Faizah Jamaluddin, Hideharu Tanaka, Kyoung Jun Song, Kentaro Kajino, Akio Kimura, Edward Pei-Chuan Huang, Ming-Ju Hsieh, Matthew Huei-Ming Ma, Wen-Chu Chiang 

PLoS Med. 2020 Oct 6;17(10):e1003360 

Background: Whether rapid transportation can benefit patients with trauma remains controversial. We determined the association between prehospital time and outcome to explore the concept of the "golden hour" for injured patients. 

Methods and findings: We conducted a retrospective cohort study of trauma patients transported from the scene to hospitals by emergency medical service (EMS) from January 1, 2016, to November 30, 2018, using data from the Pan-Asia Trauma Outcomes Study (PATOS) database. Prehospital time intervals were categorized into response time (RT), scene to hospital time (SH), and total prehospital time (TPT). The outcomes were 30-day mortality and functional status at hospital discharge. Multivariable logistic regression was used to investigate the association of prehospital time and outcomes to adjust for factors including age, sex, mechanism and type of injury, Injury Severity Score (ISS), Revised Trauma Score (RTS), and prehospital interventions. Overall, 24,365 patients from 4 countries (645 patients from Japan, 16,476 patients from Korea, 5,358 patients from Malaysia, and 1,886 patients from Taiwan) were included in the analysis. Among included patients, the median age was 45 years (lower quartile [Q1]-upper quartile [Q3]: 25-62), and 15,498 (63.6%) patients were male. Median (Q1-Q3) RT, SH, and TPT were 20 (Q1-Q3: 12-39), 21 (Q1-Q3: 16-29), and 47 (Q1-Q3: 32-60) minutes, respectively. In all, 280 patients (1.1%) died within 30 days after injury. Prehospital time intervals were not associated with 30-day mortality. The adjusted odds ratios (aORs) per 10 minutes of RT, SH, and TPT were 0.99 (95% CI 0.92-1.06, p = 0.740), 1.08 (95% CI 1.00-1.17, p = 0.065), and 1.03 (95% CI 0.98-1.09, p = 0.236), respectively. However, long prehospital time was detrimental to functional survival. The aORs of RT, SH, and TPT per 10-minute delay were 1.06 (95% CI 1.04-1.08, p < 0.001), 1.05 (95% CI 1.01-1.08, p = 0.007), and 1.06 (95% CI 1.04-1.08, p < 0.001), respectively. The key limitation of our study is the missing data inherent to the retrospective design. Another major limitation is the aggregate nature of the data from different countries and unaccounted confounders such as in-hospital management. 

Conclusions: Longer prehospital time was not associated with an increased risk of 30-day mortality, but it may be associated with increased risk of poor functional outcomes in injured patients. This finding supports the concept of the "golden hour" for trauma patients during prehospital care in the countries studied.

Prehospital Blood Transfusion During Aeromedical Evacuation of Trauma Patients in Israel: The IDF CSAR Experience

Jacob Chen, Avi Benov, Roy Nadler, Daniel N Darlington, Andrew P Cap, Ari M Lipsky, Elon Glassberg

Mil Med 2017 Mar;182(S1):47-52 

Background: Data regarding the effect of prehospital blood administration to trauma patients during short-to-moderate time evacuations is scarce. The Israel Air Force Airborne Combat Search and Rescue is the only organization that deals with aeromedical evacuation for both military and civilian casualties in Israel and the only one with the ability to give blood in the prehospital setting.

Methods: Data on packed red blood cells (PRBCs) administration in the evacuation missions from January 2003 to June 2010 were analyzed and actual transfusion practice was compared to clinical practice guidelines (CPGs).

Results: Over the studied 101 months, a total of 1,721 patients were evacuated by Combat Search and Rescue. Of these, 87 (5.1%) trauma patients were transfused with PRBC. Demographics included 83% male and 17% female with a median age of 23 years. Main mechanisms of injury included gunshot wounds (36%), motor vehicle accidents (28%), and blast injuries (24%) with an average of 2.6 injured regions per casualty. The most commonly injured body regions included lower extremities (52%), chest (45%), and abdomen (38%). Overall, 10 (11%) casualties died. Lifesaving intervention included tourniquets (27%), endotracheal intubation (24%), tube thoracostomy (24%), and needle thoracostomy (21%) times. For 98% of the patients, clinical judgment led to administration of red blood cells before indicated by the CPG. The heart rate tended to decrease during the evacuation, whereas there was no clear trend in systolic or diastolic blood pressure or shock index.

Conclusions: In our aeromedical experience, transfusion of PRBCs for trauma patients was safe, feasible, and most likely beneficial. PRBCs were administered according to the flight surgeons' clinical judgment and not in complete adherence to CPGs in most cases. Data collected from this and similar studies worldwide have led to change in CPGs with the shift from hypertensive resuscitation to hypotensive-hemostatic Remote Damage Control Resuscitation.

Fresh frozen plasma attenuates lung injury in a novel model of prolonged hypotensive resuscitation

Amanda M Chipman, Feng Wu, Shibani Pati, Alexander J Burdette, Jacob J Glaser, Rosemary A Kozar

J Trauma Acute Care Surg. 2020 Aug;89(2S Suppl 2):S118-S125 

Background: Hemorrhagic shock remains a leading cause of early death among severely injured in both civilian and military settings. As future military operations will require strategies allowing prolonged field care of the injured, we sought to develop an in vivo model of prolonged hypotensive resuscitation (PHR) and to evaluate the role of plasma-based resuscitation in this model. We hypothesized that resuscitation with fresh frozen plasma (FFP) would mitigate lung injury when compared with Hextend in a rodent model of PHR.

Methods: Mice underwent laparotomy and hemorrhagic shock (mean arterial blood pressure, 35 ± 5 mm Hg × 90 minutes) followed by PHR with either FFP or Hextend to maintain a mean arterial blood pressure of 55 mm Hg to 60 mm Hg for 6 hours. Sham animals underwent cannulation only. At the end of 6 hours, animals were euthanized, and lung tissue harvested for measurement of histopathologic injury, inflammation and permeability using hematoxylin and eosin staining, myeloperoxidase immunofluorescence staining and Evans Blue dye. Pulmonary syndecan-1 immunostaining was assessed as an indicator of endothelial cell integrity.

Results: All animals in the FFP, Hextend, and sham groups survived to the end of resuscitation. Resuscitation with FFP mitigated lung histopathologic injury compared with Hextend (histologic injury score of 4.38 ± 2.07 vs. 7.5 ± 0.93, scale of 0-9, p = 0.002) and was comparable to shams (histologic injury score of 4.0 ± 1.93, scale of 0-9, p = 0.99). Fresh frozen plasma also reduced lung inflammation (0.116 ± 0.044 vs. 0.308 ± 0.054 relative fluorescence of myeloperoxidase, p

= 0.002) and restored pulmonary syndecan-1 (0.514 ± 0.061 vs. 0.059 ± 0.021, relative syndecan-1 fluorescence, p < 0.001) when compared with Hextend. Consistently, FFP mitigated lung hyperpermeability compared with Hextend (7.30 ± 1.34 μg vs. 14.91 ± 5.55 μg Evans blue/100 mg lung tissue, p = 0.005).

Conclusion: We have presented a novel model of PHR of military relevance to the prolonged field care environment. In this model, FFP maintains its pulmonary protective effects using a PHR strategy compared with Hextend, which supports the need for further development and implementation of plasma-based resuscitation in the forward environment.

Aortic balloon occlusion (REBOA) in pelvic ring injuries: preliminary results of the ABO Trauma Registry

Federico Coccolini, Marco Ceresoli, David T McGreevy, Mitra Sadeghi, Artai Pirouzram, Asko Toivola, Per Skoog, Koji Idoguchi, Yuri Kon, Tokiya Ishida, Yosuke Matsumura, Junichi Matsumoto, Viktor Reva, Mariusz Maszkowski, Paola Fugazzola, Matteo Tomasoni, Enrico Cicuttin, Luca Ansaloni, Claudia Zaghi, Maria Grazia Sibilla, Camilla Cremonini, Adam Bersztel, Eva-Corina Caragounis, Mårten Falkenberg, Lauri Handolin, George Oosthuizen, Endre Szarka, Vassil Manchev, Tongporn Wannatoop, Sung Wook Chang, Boris Kessel, Dan Hebron, Gad Shaked, Miklosh Bala, Carlos A Ordoñez, Peter Hibert-Carius, Massimo Chiarugi, Kristofer F Nilsson, Thomas Larzon, Emiliano Gamberini, Vanni Agnoletti, Fausto Catena, Tal M Hörer

Updates Surg 2020 Jun;72(2):527-536 

EndoVascular and Hybrid Trauma Management (EVTM) has been recently introduced in the treatment of severe pelvic ring injuries. This multimodal method of hemorrhage management counts on several strategies such as the REBOA (resuscitative endovascular balloon occlusion of the aorta). Few data exist on the use of REBOA in patients with a severely injured pelvic ring. The ABO (aortic balloon occlusion) Trauma Registry is designed to capture data for all trauma patients in hemorrhagic shock where management includes REBOA placement. Among all patients included in the ABO registry, 72 patients presented with severe pelvic injuries and were the population under exam. 66.7% were male. Mean and median ISS were respectively 43 and 41 (SD ± 13). Isolated pelvic injuries were observed in 12 patients (16.7%). Blunt trauma occurred in 68 patients (94.4%), penetrating in 2 (2.8%) and combined in 2 (2.8%). Type of injury: fall from height in 15 patients (23.1%), traffic accident in 49 patients (75.4%), and unspecified impact in 1 patient (1.5%). Femoral access was gained pre-hospital in 1 patient, in emergency room in 43, in operating room in 12 and in angio-suite in 16. REBOA was positioned in zone 1 in 59 patients (81,9%), in zone 2 in 1 (1,4%) and in zone 3 in 12 (16,7%). Aortic occlusion was partial/periodical in 35 patients (48,6%) and total occlusion in 37 patients (51,4%). REBOA associated morbidity rate: 11.1%. Overall mortality rate was 54.2% and early mortality rate (≤ 24 h) was 44.4%. In the univariate analysis, factors related to early mortality (≤ 24 h) are lower pH values (p = 0.03), higher base deficit (p = 0.021), longer INR (p = 0.012), minor increase in systolic blood pressure after the REBOA inflation (p = 0.03) and total aortic occlusion (p = 0.008). None of these values resulted significant in the multivariate analysis. In severe hemodynamically unstable pelvic trauma management, REBOA is a viable option when utilized in experienced centers as a bridge to other treatments; its use might be, however, accompanied with severe-to-lethal complications.

Out-of-Hospital Tranexamic Acid for Traumatic Brain Injury 

David C Cone, Daniel W Spaite, Timothy J Coats 

JAMA. 2020 Sep 8;324(10):946-947. doi: 10.1001/jama.2020.9244 

No abstract available

The compensatory reserve: potential for accurate individualized goal-directed whole blood resuscitation

Victor A Convertino, Natalie J Koons Transfusion. 2020 Jun;60 Suppl 3:S150-S157

Hemorrhagic shock can be mitigated by timely and accurate resuscitation designed to restore adequate delivery of oxygen (DO2 ). Current doctrine of using systolic blood pressure (SBP) as a guide for resuscitation can be associated with increased morbidity. The compensatory reserve measurement (CRM) is a novel vital sign based on the recognition that the sum of all mechanisms that contribute to the compensatory response to hemorrhage reside in features of the arterial pulse waveform. CRM can be assessed continuously and non-invasively in real time. Compared to standard vital signs, CRM provides an early, as well as more sensitive and specific, indicator of patient hemorrhagic status since the activation of compensatory mechanisms occurs immediately at the onset of blood loss. Recent data obtained from our laboratory experiments on non-human primates have demonstrated that CRM is linearly related to DO2 during controlled progressive hemorrhage and subsequent whole blood resuscitation. 

We used this relationship to determine that the time of hemodynamic decompensation (i.e., CRM = 0%) is defined by a critical DO2 at approximately 5.3 mL O2 ∙kg-1 ∙min-1 . We also demonstrated that a target CRM of 35% during whole blood resuscitation only required replacement of 40% of the total blood volume loss to adequately sustain a DO2 more than 50% (i.e., 8.1 mL O2 ∙kg-1 ∙min-1 ) above critical DO2 (i.e., threshold for decompensated shock) while maintaining hypotensive resuscitation (i.e., SBP at ~90 mmHg). Consistent with our hypothesis, specific values of CRM can be used to accurately maintain DO2 thresholds above critical DO2 , avoiding the onset of hemorrhagic shock with whole blood resuscitation.

Wearable Sensors Incorporating Compensatory Reserve Measurement for Advancing Physiological Monitoring in Critically Injured Trauma Patients (Need link)

Victor A Convertino, Steven G Schauer, Erik K Weitzel, Sylvain Cardin, Mark E Stackle, Michael J Talley, Michael N Sawka, Omer T Inan 

Sensors (Basel). 2020 Nov 10;20(22):6413 

Abstract 

Vital signs historically served as the primary method to triage patients and resources for trauma and emergency care, but have failed to provide clinically-meaningful predictive information about patient clinical status. In this review, a framework is presented that focuses on potential wearable sensor technologies that can harness necessary electronic physiological signal integration with a current state-of-the-art predictive machine-learning algorithm that provides early clinical assessment of hypovolemia status to impact patient outcome. The ability to study the physiology of hemorrhage using a human model of progressive central hypovolemia led to the development of a novel machine-learning algorithm known as the compensatory reserve measurement (CRM). Greater sensitivity, specificity, and diagnostic accuracy to detect hemorrhage and onset of decompensated shock has been demonstrated by the CRM when compared to all standard vital signs and hemodynamic variables. The development of CRM revealed that continuous measurements of changes in arterial waveform features represented the most integrated signal of physiological compensation for conditions of reduced systemic oxygen delivery. In this review, detailed analysis of sensor technologies that include photoplethysmography, tonometry, ultrasound-based blood pressure, and cardiogenic vibration are identified as potential candidates for harnessing arterial waveform analog features required for real-time calculation of CRM. The integration of wearable sensors with the CRM algorithm provides a potentially powerful medical monitoring advancement to save civilian and military lives in emergency medical settings.

Validating Clinical Threshold Values for a Dashboard View of the Compensatory Reserve Measurement for Hemorrhage Detection

Victor A Convertino, Mallory R Wampler, Michael Johnson, Abdul Alarhayem, Tuan D Le, Susannah Nicholson, John G Myers, Kevin K Chung, Katie R Struck, Camaren Cuenca, Brian J Eastridge

J Trauma Acute Care Surg 2020 Jan 15;Epub ahead of print 

Abstract

Background: Compensatory Reserve Measurement (CRM) is a novel noninvasive monitoring technology designed to assess physiologic reserve using feature interrogation of arterial pulse waveforms. This study was conducted to validate clinically relevant CRM values with a simplified color-coded dashboard view.

Methods: We performed a prospective observational study of 300 injured patients admitted to a level I trauma center. CRM was recorded upon ER admission. Data collected to complement the analysis included Patient demographics, vital signs, life-saving interventions (LSI), injury severity score (ISS) and outcomes were recorded. Threshold values of CRM were analyzed for predictive capability of hemorrhage.

Results: 285 patients met inclusion criteria. Mean age of the population was 47 years and 67% were male. Hemorrhage was present in 32 (11%) and LSI was performed in 40 (14%) patients. Transfusion of packed red blood cells (PRBC) was administered in 33 (11.6%) patients, and 21 (7.4%) were taken to the operating room for surgical or endovascular control of hemorrhage.

Statistical analyses were performed to identify optimal threshold values for 3 zones of CRM to predict hemorrhage. Optimal levels for red, yellow, and green areas of the dashboard view were stratified as follows: red if CRM<30%, yellow if CRM=30-59%, and green if CRM≥60%. Odds of hemorrhage increased by 12-fold (OR, 12.2; 95%CI, 3.8-38.9) with CRM<30% (red) and 6.5- fold (OR, 6.5; 95%CI, 2.7-15.9) with CRM=30-59% (yellow) when compared to patients with CRM≥60%. ROCAUC for 3-zone CRM was similar to that of continuous CRM (0.77 vs. 0.79), but further increased the ability to predict hemorrhage after adjusting for ISS (ROCAUC = 0.87).

Conclusion: A 3-zone CRM could be a potentially useful predictor of hemorrhage in trauma patients with added capabilities of continuous monitoring and a real-time ISS assessment. These data substantiate easily interpretable threshold dashboard values for triage with potential to improve injury outcomes.

Level of evidence: Diagnostic, Level II.

Whole blood transfusion versus component therapy in trauma resuscitation: a systematic review and meta-analysis 

Ellen Crowe, Stacia M DeSantis, Austin Bonnette, Jan O Jansen, Jose-Miguel Yamal, John B Holcomb, Claudia Pedroza, John A Harvin, Marisa B Marques, Elenir B C Avritscher, Henry E Wang 

J Am Coll Emerg Physicians Open. 2020 May 29;1(4):633-641 

Background: Patients with hemorrhagic shock from trauma often require balanced blood product transfusion with red blood cells, plasma, and platelets. Resuscitation with whole blood resuscitation is becoming a common practice. We performed a systematic review and meta-analysis of studies comparing whole blood transfusion with balanced component therapy in patients suffering from traumatic hemorrhagic shock. 

Methods: We searched MEDLINE Ovid, EMBASE, and the Cochrane Library for human studies comparing whole blood with component blood therapy published from January 2007 to June 2019. We included studies from both civilian and military settings and that reported 24-hour, in-hospital, or 30-day mortality. We followed the Preferred Reporting Items in Systematic Reviews and Meta-Analyses (PRISMA) guidelines, assessing study quality, publication bias, and heterogeneity. We used meta-analytic models to determine the associations (odds ratio [OR] with 95% confidence interval [CI]) between whole blood transfusion and (1) 24-hour mortality, and (2) in-hospital or 30-day mortality. 

Results: A total of 1759 identified studies, 12 (reporting on n = 8431 patients) met inclusion criteria. There was heterogeneity in the design, setting, interventions, and outcomes of the studies. On meta-analysis, whole blood transfusion was not associated with 24-hour mortality (OR = 0.83; 95% CI = 0.56-1.24) or in-hospital/30-day mortality (OR = 0.79; 95% CI = 0.48-1.31). 

Conclusion: In this systematic review and meta-analysis, compared with conventional component transfusion, whole blood was not associated with 24-hour or in-hospital mortality. However, there were important limitations with and heterogeneity among the primary studies. Additional study is needed to determine the effectiveness of whole blood.

The ticking clock: does actively making an enhanced care team aware of the passage of time improve pre-hospital scene time following traumatic incidents?

L Curtis, E Ter Avest, J Griggs, J Wiliams, R M Lyon

Scand J Trauma Resusc Emerg Med 2020 Apr 29;28(1):31 

Introduction: Pre-hospital enhanced care teams like Helicopter Emergency Medical Services (HEMS) are often dispatched to major trauma patients, including patients with traumatic brain injuries and those with major haemorrhage. For these patients, minimizing the time to definitive care is vital. The aim of this study was to determine whether increased awareness of elapsed on scene time produces a relevant time performance improvement for major trauma patients attended by HEMS, and weather introducing such a timer was feasible and acceptable to clinicians.

Methods: We performed a prospective cohort study of all single casualty traumatic incidents attended by Air Ambulance Kent Surrey Sussex (AAKSS) between 15 October 2016 and 23 May 2017 to test if introduction of a prompting scene timer within the service resulted in a reduction in pre-hospital scene times.

Results: The majority of the patients attended were male (74%) and sustained blunt trauma (92%). Overall, median scene time was 25.5 [IQR16.3] minutes before introduction of the scene timer and 23.0 [11.0] minutes after introduction, p = 0.13). Scene times for patients with a GCS

< 8 and for patients requiring prehospital anaesthesia were significantly lower after introduction of the timer (28 [IQR 14] vs 25 [1], p = 0.017 and 34 [IQR 13] vs 28 [IQR11] minutes, p = 0.007 respectively). The majority of clinicians felt the timer made them more aware of passing time (91%) but that this had not made a difference to scene time (62%) or their practice (57%).

Conclusion: Audible scene timers may have the potential to reduce pre-hospital scene time for certain single casualty trauma patients treated by a HEMS team, particularly for those patients needing pre-hospital anaesthesia. Regular use of on-scene timers may improve outcomes by reducing time to definitive care for certain subgroups of trauma patients.

Spinal Immobilization in Disasters: A Systematic Review 

Joseph L Cuthbertson, Eric S Weinstein 

Prehosp Disaster Med. 2020 Aug;35(4):406-411 

Abstract 

In response to the International Liaison Committee on Resuscitation (ILCOR; Niel, Belgium) release of an updated recommendation related to out-of-hospital spinal immobilization (SI) practice in 2015, a systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist of English-language studies published from January 2000 through July 2019 on the use of SI in resource-scarce environments (RSEs). Studies meeting the following criteria were included in the analysis: peer-reviewed statistical studies or reports detailing management of potential traumatic spinal injury in RSE, civilian, and military environments; as well as consensus clinical guidelines, academic center, or professional association protocols or policy statements detailing management of potential traumatic spinal injury in RSE, civilian, and military environments; statistical analysis; and subsequent management of spinal injuries after mass-casualty incidents, in complex humanitarian events or conflict zones, low-to middle-income countries, or prolonged transport times published by government and non-government organizations. Studies excluded from consideration were those not related to a patient with a potential traumatic spinal injury after a mass-casualty incident, in complex humanitarian event or conflict zones, in low-to middle-income countries, or with prolonged transport times.There were one thousand twenty-nine (1029) studies initially identified. After removal of duplicates, nine hundred-nineteen (919) were screened with eight hundred sixty-three (863) excluded. The remaining fifty-six (56) received further review with fourteen (14) selected studies achieving inclusion. The reviewed articles comprised six (6) types of studies and represented research from institutions in seven (7) different countries (Israel, United States, Haiti, Wales, Pakistan, China, and Iran). Thirteen (13) references were case reports/narrative reviews, policy statements, retrospective observational studies, narrative literature reviews, scoping reviews, and one systematic review. The majority of literature describing spinal cord injury was predominantly associated with earthquakes and blast-related disasters. There were no SI evidence-based clinical guidelines (EBG) in RSE. Information was obtained that could be used to formulate statements in a modified Delphi study to present to experts to obtain consensus SI EBG in RSE.

Perioperative intravenous low-dose ketamine for neuropathic pain after major lower back surgery: A randomized, placebo-controlled study

Christoph Czarnetzki 1 2, Jules Desmeules 2 3, Enrico Tessitore 2 4, Antonio Faundez 5,

Jocelyne Chabert 3, Youssef Daali 2 3, Roxane Fournier 1 2, Elise Dupuis-Lozeron 6,

Christine Cedraschi 2 3, Martin Richard Tramèr Eur J Pain 2020 Mar;24(3):555-567 

Abstract

Background: Chronic pain after major lower back surgery is frequent. We investigated in adults the effect of perioperative low-dose ketamine on neuropathic lower back pain, assessed by the DN4 questionnaire, 6 and 12 months after major lower back surgery.

Methods: In this single-centre randomized trial, 80 patients received intravenous ketamine 0.25 mg/kg preoperatively, followed by 0.25 mg kg-1 hr-1 intraoperatively, and 0.1 mg kg-1 hr-1 from 1 hr before the end of surgery until the end of recovery room stay; 80 controls received placebo.

Results: Preoperatively, 47.4% of patients in the ketamine group and 46.3% in the placebo group had neuropathic pain; 10% and 3.8%, respectively, were using strong opioids. At the end of the infusion, the median cumulative dose of ketamine was 84.8 mg (IQR 67.4-106.7) and the median plasma level was 97 ng/ml (IQR 77.9-128.0). At 6 months, 28.8% of patients in the ketamine group and 23.5% in the placebo group had neuropathic pain (absolute difference, 5.2%; 95% CI -10.7 to 21.1; p = .607). At 12 months, 26.4% of patients in the ketamine group and 17.9% in the placebo group had neuropathic pain (absolute difference 8.5%; 95% CI -6.7 to 23.6; p = .319).

Conclusions: In this patient population with a high prevalence of neuropathic lower back pain undergoing major lower back surgery, a perioperative intravenous low-dose ketamine infusion did not have an effect on the prevalence of neuropathic lower back pain at 6 or 12 months postoperatively.

Significance: We were unable to show any analgesic benefit of a short-term perioperative ketamine infusion as an adjuvant to multimodal analgesia in patients with a high prevalence of neuropathic lower back pain undergoing major back surgery. Based on these data, the widespread opinion that ketamine is universally analgesic across different pain conditions must be challenged.

It's In The Bag: Tidal Volumes in Adult and Pediatric Bag Valve Masks Benjamin Dafilou, Daniel Schwester, Nathan Ruhl, Andreia Marques-Baptista

West J Emerg Med 2020 Apr 27;21(3):722-726 

Introduction: A bag valve mask (BVM) is a life saving device used by all levels of health care professionals during resuscitative care. We focus most of our time optimizing the patient's position, firmly securing the mask, and frequency of ventilations. However, despite our best efforts to control these factors, we may still be precipitating harm to the patient. Multiple studies have shown the tidal volumes typically delivered by the adult BVM are often higher than recommended for lung-protective ventilation protocols. In this study we measure and compare the ventilation parameters delivered by the adult and pediatric BVM ventilators.

Methods: A RespiTrainer Advance® adult mannequin was used to simulate a patient. Healthcare providers were directed to manually ventilate an intubated mannequin for two minutes using adult and pediatric sized BVMs. Tidal volume, minute ventilation, peak pressure, and respiration rate was recorded.

Results: The adult BVM provided a mean tidal volume of 807.7mL versus the pediatric BVM providing 630.7mL, both of which exceeded the upper threshold of 560mL of tidal volume necessary for lung protective ventilation of an adult male with an ideal body weight of 70kg. The adult BVM exceeded this threshold by 44.2% versus the pediatric BVM's 12.6% with 93% of participants exceeding the maximum threshold with the adult BVM and 82.3% exceeding it with the pediatric BVM.

Conclusion: The pediatric BVM in our study provided far more consistent and appropriate ventilation parameters for adult patients compared to an adult BVM, but still exceeded the upper limits of lung protective ventilation parameters. The results of this study highlight the potential dangers in using an adult BVM due to increased risk of pulmonary barotrauma. These higher tidal volumes can contribute to lung injury. This study confirms that smaller BVMs may provide safer ventilatory parameters. Future studies should focus on patient-centered outcomes with BVM.

Blast polytrauma with hemodynamic shock, hypothermia, hypoventilation and systemic inflammatory response: description of a new porcine model

Albin Dahlquist, Louise Elander Degerstedt, Erik von Oelreich, Andreas Brännström, Jenny Gustavsson, Ulf P Arborelius, Mattias Günther

Eur J Trauma Emerg Surg. 2020 Aug 30;1-9 

Purpose: In the past decade blast injuries have become more prevalent. Blast trauma may cause extensive injuries requiring improved early resuscitation and prevention of haemorrhage. Randomized prospective trials are logistically and ethically challenging, and large animal models are important for further research efforts. Few severe blast trauma models have been described, which is why we aimed to establish a comprehensive polytrauma model in accordance with the criteria of the Berlin definition of polytrauma and with a survival time of > 2 h. Multiple blast injuries to the groin and abdomen were combined with hypoperfusion, respiratory and metabolic acidosis, hypoventilation, hypothermia and inflammatory response. The model was compared to lung contusion and haemorrhage.

Methods: 16 landrace swine (mean weight 60.5 kg) were randomized to "control" (n = 5), "chest trauma/hem" by lung contusion and class II haemorrhage (n = 5), and "blast polytrauma" caused by multiple blast injuries to the groin and abdomen, class II haemorrhage, lipopolysaccharide (LPS) infusion and hypothermia 32 °C (n = 6).

Results: The blast polytrauma group had an Injury Severity Score of 57 which resulted in haemodynamic shock, hypothermia, respiratory and metabolic acidosis and inflammatory response. The chest trauma/hem group had an Injury Severity Score of 9 and less profound physiologic effects. Physiologic parameters presented a dose-response relationship corresponding to the trauma levels.

Conclusion: A comprehensive blast polytrauma model fulfilling the Berlin polytrauma criteria, with a high trauma load and a survival time of > 2 h was established. A severe, but consistent, injury profile was accomplished enabling the addition of experimental interventions in future studies, particularly of immediate resuscitation efforts including whole blood administration, trauma packing and haemostasis.

Prehospital emergency thoracotomy performed by helicopter emergency medical service team: A case report

Tomasz Darocha, Sylweriusz Kosinski, Wojciech Serednicki, Tomasz Derkowski, Pawel Podsiadlo, Jan Szpor, Tomasz Sanak, Robert Galazkowski

Ulus Travma Acil Cerrahi Derg 2019 May;25(3):303-306 

Emergency thoracotomy can be a life-saving procedure in critically injured patients who present with chest injuries. Currently, the indications for an on-the-scene thoracotomy are penetrating trauma of the chest or upper abdomen with cardiac arrest that has occurred in the presence of an emergency team or within 10 minutes prior to their arrival. The indications for an emergency thoracotomy in blunt chest trauma are less clearly defined. In the present case, a helicopter emergency medical service (HEMS) team performed an emergency thoracotomy at the scene. To the best of our knowledge, it is the first description of such a procedure in Poland. A 41-year- old male was crushed in a tractor accident. Though all available measures were taken, a sudden cardiac arrest occurred. The HEMS team performed an emergency thoracotomy at the scene as an integral part of prehospital cardiopulmonary arrest management. The patient survived, and was later discharged from the hospital in good physical condition. No neurological deficit was identified (cerebral performance category 1). The patient returned to his previous activities with no complications or deficits. The presence of a fully trained crew allows for the performance of a potentially critical on-the-scene emergency thoracotomy. In a well-selected group of patients with blunt thoracic injury, a prehospital emergency thoracotomy may be a significant and life-saving procedure.

Prolonged Stabilization During a Mass Casualty Incident at Sea in the Era of Distributed Maritime Operations 

William G Day, Elizabeth Cooper, Khanh Phung, Benjamin Miller, Joseph DuBose, Andrew H Lin 

Mil Med. 2020 Dec 30;185(11-12):2192-2197 

Abstract 

In August 2017, the USS Bataan received a mass casualty incident (MCI) of 6 foreign special forces operators after a helicopter crash. All 6 patients were medically evacuated successfully to the USS Bataan, and all patients survived and were successfully returned to their allied country. Four of the patients received whole blood with 2 receiving over 10 units of blood or massive transfusions. One patient required 44 units of blood, and at 1 point in his resuscitation, he received 12 units of whole blood every 30 minutes. Due to administrative factors outside of the ship's control, these 6 patients had prolonged stabilization during the MCI. This factor differentiates this MCI on the USS Bataan from previous cases. Internal medicine trained physicians with their expertise in inpatient care, postsurgical management, and critical care were instrumental in sustaining these casualties in this prolonged stabilization environment. In the era of distributed maritime operations, where casualty-receiving ships will experience more geographic and resource isolation, there is a potential for the need for prolonged stabilization above the 6 to 12-hour window typical of role II platforms. The known increase in cardiac and pulmonary morbidity and mortality with medical evacuation delay highlights the importance of internal medicine physicians in the role II setting. It is critical that we emphasize the inpatient and critical care principles of these patients in the prolonged field care environment.

Use of ketamine for prehospital pain control on the battlefield: A systematic review

Gaël de Rocquigny, Christophe Dubecq, Thibault Martinez, John Peffer, Amandine Cauet, Stéphane Travers, Pierre Pasquier

J Trauma Acute Care Surg 2020 Jan;88(1):180-185 

Abstract

Background: Intravenous ketamine is commonly used for pain management in the civilian prehospital setting. Several studies have evaluated its effectiveness in the military setting. To date, there has been no report reviewing the published data on the use of ketamine in this context. The objective of this systematic review was to analyze the content and quality of published data on the use of ketamine for prehospital pain management in military trauma.

Methods: The MEDLINE database was searched for studies on ketamine use in combat prehospital settings, at point of injury or during evacuation, published between 2000 and 2019. The systematic review was conducted following PRISMA guidelines, and the protocol was registered on PROSPERO (CRD42019115728). Civilian reports and case series lacking systematic data collection were excluded.

Results: Eight studies were included with 2029 casualties receiving ketamine. All but one were American reports from Afghanistan and Iraq conflicts. Studies implied retrospective cohorts or prospective observational analysis. Ketamine use rose from 3.9% during the period preceding its addition to the Tactical Combat Casualty Care guidelines in 2012 to 19.8% thereafter. It was the most common analgesic administered (up to 52% of casualties) in one of the studies.

Ketamine was more likely given during tactical medical evacuation when no analgesic was provided at the point of injury. The median total intravenous dose was 50 mg. Pain intensity decreased from moderate or severe to mild or none, sometimes after only one dose. In one study, ketamine administration during tactical evacuation was associated with increased systolic blood pressure as opposed to morphine. Incoherent speech, extremity movements, and hallucinations were the main adverse events reported.

Conclusion: Published data on ketamine use in military trauma are rare and heterogeneous. Though, all studies tend to strengthen the belief in the efficacy and safety of ketamine when given at 50-mg to 100-mg intravenous for prehospital analgesia in combat casualties.

Level of evidence: Systematic Review, Level IV

Systematic review and meta-analysis comparing ventilatory support in chemical, biological and radiological emergencies 

Israel Baptista de Souza Borges, Magali Rezende de Carvalho, Marcel de Souza Quintana, Alexandre Barbosa de Oliveira 

Rev Lat Am Enfermagem. 2020;28:e3347 

Objective: to compare the mean development time of the techniques of direct laryngoscopy and insertion of supraglottic devices; and to evaluate the success rate in the first attempt of these techniques, considering health professionals wearing specific personal protective equipment (waterproof overalls; gloves; boots; eye protection; mask). 

Method: meta-analysis with studies from LILACS, MEDLINE, CINAHL, Cochrane, Scopus and Web of Science. The keywords were the following: personal protective equipment; airway management; intubation; laryngeal masks. 

Results: in the "reduction of the time of the procedures" outcome, the general analysis of the supraglottic devices in comparison with the orotracheal tube initially presented high heterogeneity of the data (I2= 97%). Subgroup analysis had an impact on reducing heterogeneity among the data. The "laryngeal mask as a guide for orotracheal intubation" subgroup showed moderate heterogeneity (I2= 74%). The "2ndgeneration supraglottic devices" subgroup showed homogeneity (I2= 0%). All the meta-analyses favored supraglottic devices. In the "success in the first attempt" outcome, moderate homogeneity was found (I2= 52%), showing a higher proportion of correct answers for supraglottic devices. 

Conclusion: in the context of chemical, biological or radiological disaster, the insertion of the supraglottic device proved to be faster and more likely to be successful by health professionals. PROSPERO record (CRD42019136139).

Rare Use of Posterolateral Thoracotomy in an Austere Environment

Rebekah J Devasahayam, Robert A Fabich, Currie A Tighe, Tyson E Becker Mil Med 2020 Mar 2;185(3-4):530-531 

Abstract

A 25-year-old local national male presented to a split Forward Surgical Team after impalement of the posterior chest with a metal fragment. The patient was hemodynamically normal, but no imaging was available to determine the depth of penetration or the size of the internal portion of the fragment. This case represents a rare indication for posterolateral thoracotomy in an austere trauma setting.

Best practices for emergency surgical airway: A systematic review

Elliana K DeVore, Andrew Redmann, Rebecca Howell, Sid Khosla

Laryngoscope Investig Otolaryngol 2019 Nov 19;4(6):602-608 

Abstract

Objective: In the case of an emergency surgical airway, current guidelines state that surgical cricothyrotomy is preferable to tracheotomy. However, complications associated with emergency cricothyrotomy may be more frequent and severe. We systematically reviewed the English literature on emergency surgical airway to elicit best practices.

Methods: PubMed, Embase, MEDLINE, and the Cochrane Library were searched from inception to January 2019 for studies reporting emergency cricothyrotomy and tracheotomy outcomes. All English-language retrospective analyses, systematic reviews, and meta-analyses were included. Case reports were excluded, as well as studies with pediatric, nonhuman, or nonliving subjects.

Results: We identified 783 articles, and 20 met inclusion criteria. Thirteen evaluated emergency cricothyrotomy and included 1,219 patients (mean age = 39.8 years); 4 evaluated emergency tracheotomy and included 342 patients (mean age = 46.0 years); 2 evaluated both procedures. The rate of complications with both cricothyrotomy and tracheotomy was comparable. The most frequent early complications were failure to obtain an airway (1.6%) and hemorrhage (5.6%) for cricothyrotomy and tracheotomy, respectively. Airway stenosis was the most common long-term complication, occurring at low rates in both procedures (0.22-7.0%).

Conclusions: Complications associated with emergency cricothyrotomy may not occur as frequently as presumed. Tracheotomy is an effective means of securing the airway in an emergent setting, with similar risk for intraoperative and postoperative complications compared to cricothyrotomy. Ultimately, management should depend on clinician experience and patient characteristics.

Level of evidence: IV

Evaluation of Nasopharyngeal Airway to Facilitate Nasotracheal Intubation

Vinay R Dhakate, Amol Prakash Singam, Harshvardhan S Bharadwaj

Ann Maxillofac Surg. Jan-Jun 2020;10(1):57-60 

Background and aims: Nasotracheal intubation is the most common method of airway management in oral and maxillofacial surgery patients. However, many times, it is associated with bleeding resulting from trauma to nasopharyngeal mucosa. We conducted this study to determine the effectiveness of nasopharyngeal airway (NPA) to easily facilitate the nasopharyngeal insertion and to reduce the trauma during nasotracheal intubation.

Methods: A total of 120 patients scheduled for elective oral and maxillofacial surgery requiring nasotracheal intubation were randomly divided into two groups of 60 each, after preparation with xylometazoline drops intranasally, lubrication with lignocaine jelly, and thermosoftening of the tip of the endotracheal tube (ETT). In group NPA, dilatation of the nasal cavity was done with NPA before nasotracheal intubation and in Group C, nasotracheal intubation was done without dilatation of the nasal cavity. The smoothness of insertion of ETT was graded on a 4‑point rating scale. Assessment of bleeding into nasopharynx was confirmed during laryngoscopy and was also graded with 4‑point scale.

Results: In the NPA group, all the 60 (100%) patients had smooth or relatively smooth (Grade 0 or 1) insertion compared to 51 (85%) patients in the control group (P < 0.0001). Eighteen (30%) patients had mild (Grade 1) bleeding and one (1.67%) patient had moderate bleeding (Grade 2) in the control group, whereas only four (6.67%) patients in the NPA group had mild (Grade 1) bleeding (P = 0.0005).

Conclusion: Dilatation of nasal cavity with NPA significantly eases the insertion of ETT into the nasopharynx and also significantly decreases the incidence and severity of trauma and bleeding during nasotracheal intubation.

Tranexamic acid administration in the field does not affect admission thromboelastography after traumatic brain injury

Alexandra L Dixon, Belinda H McCully, Elizabeth A Rick, Elizabeth Dewey, David H Farrell, Laurie J Morrison, Jason McMullan, Bryce R H Robinson, Jeannie Callum, Brian Tibbs, David J Dries, Jonathan Jui, Rajesh R Gandhi, John S Garrett, Myron L Weisfeldt, Charles E Wade, Tom P Aufderheide, Ralph J Frascone, John M Tallon, Delores Kannas, Carolyn Williams, Susan E Rowell, Martin A Schreiber

J Trauma Acute Care Surg. 2020 Nov;89(5):900-907 

Background: No Food and Drug Administration-approved medication improves outcomes following traumatic brain injury (TBI). A forthcoming clinical trial that evaluated the effects of two prehospital tranexamic acid (TXA) dosing strategies compared with placebo demonstrated no differences in thromboelastography (TEG) values. We proposed to explore the impact of TXA on markers of coagulation and fibrinolysis in patients with moderate to severe TBI.

Methods: Data were extracted from a placebo-controlled clinical trial in which patients 15 years or older with TBI (Glasgow Coma Scale, 3-12) and systolic blood pressure of ≥90 mm Hg were randomized prehospital to receive placebo bolus/placebo infusion (placebo), 1 g of TXA bolus/1 g of TXA infusion (bolus maintenance), or 2 g of TXA bolus/placebo infusion (bolus only). Thromboelastography was performed, and coagulation measures including prothrombin time, activated partial thromboplastin time, international ratio, fibrinogen, D-dimer, plasmin-antiplasmin (PAP), thrombin antithrombin, tissue plasminogen activator, and plasminogen activator inhibitor 1 were quantified at admission and 6 hours later.

Results: Of 966 patients receiving study drug, 700 had laboratory tests drawn at admission and 6 hours later. There were no statistically significant differences in TEG values, including LY30, between groups (p > 0.05). No differences between prothrombin time, activated partial thromboplastin time, international ratio, fibrinogen, thrombin antithrombin, tissue plasminogen activator, and plasminogen activator inhibitor 1 were demonstrated across treatment groups. Concentrations of D-dimer in TXA treatment groups were less than placebo at 6 hours (p < 0.001). Concentrations of PAP in TXA treatment groups were less than placebo on admission (p < 0.001) and 6 hours (p = 0.02). No differences in D-dimer and PAP were observed between bolus maintenance and bolus only.

Conclusion: While D-dimer and PAP levels reflect a lower degree of fibrinolysis following prehospital administration of TXA when compared with placebo in a large prehospital trial of patients with TBI, TEG obtained on admission and 6 hours later did not demonstrate any differences in fibrinolysis between the two TXA dosing regimens and placebo.

J Spec Oper Med. Fall 2020;20(3):128-134

Far Forward Gaps in Hemorrhagic Shock and Prolonged Field Care: An Update of ALM Fluid Therapy for Field Use

Geoffrey P Dobson, Hayley L Letson 

Abstract

Future expeditionary missions are expected to occur in more remote austere environments where combat medics and casualties may have to wait up to 7 days before resupply or safe evacuation. Currently, there is no effective fluid therapy for hemorrhagic shock (HS) at the point-of-injury and continuum-of-care over this extended period. We have been developing a small-volume IV or IO ALM therapy for noncompressible HS and have shown in preclinical models that it extends survival to 3 days, reduces abdominal bleeding by 60%, blunts inflammation, corrects coagulopathy, preserves platelet function, and prevents immunodeficiency. The ALM-survival phenotype is associated with an upregulation of the master genes of metabolism and mitochrondrial biogenesis in heart and brain and a downregulation in the periphery. Future translational studies will investigate the timing and nature of the "switch" and extend survival to 7 days. We will also discuss some of the controversies of ALM resuscitation in pigs, present our Systems Hypothesis of Trauma (SHOT), and discuss future clinical safety trials before field use.

Impact of Early Tranexamic Acid Administration on Overall Blood Product Utilization at 24 Hours

Alisha Douglas, Donna Faviere, Amber Gallo, Ashley VanderSchaaf, Ward Wall, Kayla Wilson, Ashley Young

J Trauma Nurs Mar/Apr 2020;27(2):66-70 

Antifibrinolytics have demonstrated a mortality benefit in trauma patients when utilized early after injury. In line with recent literature, the authors hypothesize that early tranexamic acid (TXA) administration will decrease overall blood product administration at 24 hr. This is a retrospective cohort evaluation of 65 trauma patients admitted and discharged between May 1, 2015, and December 31, 2017, who received packed red blood cells (PRBCs) and TXA within 3 hr following injury. The primary outcome was overall PRBC utilization at 24 hr when TXA was administered less than 1 hr of injury compared with 1-3 hr of injury. A subgroup analysis compared PRBC usage at 24 hr when PRBC to TXA administration time was less than 30 min compared with 30 min or more. During the study time, 15 patients received TXA early, less than 1 hr from injury, and 50 patients received TXA within 1-3 hr of injury. Patients received a median of 7 units of PRBCs in the early group and 8 units in the standard group (p = .64) at 24 hr.

Patients who received TXA less than 30 min after first PRBC received a median of 6 units at 24 hr compared with 9 units when PRBC to TXA time was 30 min or more (p = .014). There was no difference in PRBCs at 24 hr in patients who received TXA early compared with 1-3 hr from injury. There was a significant increase in PRBC requirement at 24 hr when patients received TXA 30 min or more from first PRBC. Further inquiry into the optimal timing of TXA administrated is needed.

Use of the intubating laryngeal mask airway in the emergency department: A ten-year retrospective review

Brian E Driver, Marc Martel, Tarissa Lai, Tracy A Marko, Robert F Reardon Am J Emerg

Med 2020 Jul;38(7):1367-1372 

Abstract

Background: Extraglottic devices, such as the intubating laryngeal mask airway (ILMA), facilitate ventilation and oxygenation and are useful for emergency airway management, especially as rescue devices. In the operating room setting the ILMA has been highly successful. However, its performance in the ED has not been described. We sought to describe the indications for and success of the ILMA when used in the ED.

Methods: We performed retrospective, observational study of patients who had an LMA® Fastrach™ (hereafter termed ILMA) placed in a single ED between 2007 and 2017. Patients were identified by keyword search of ED notes in the electronic medical record. Trained abstractors reviewed charts and videos to determine patient characteristics, indication for ILMA placement, success of oxygenation and ventilation, intubation methods and success, and complications related to the device.

Results: During the study period 218 patients had an ILMA placed in the ED. The ILMA was used as a primary device in 118 patients (54%), and as a rescue device in 100 patients (46%). The median number of ILMA uses per faculty physician during the study period was 3. The ILMA oxygenated and ventilated successfully in 212 instances (98%), including 96 times (96%) when used as a rescue airway. Failure of oxygenation was due to tracheal injury (2), abnormal laryngeal inlet anatomy (2), or poor operator technique (1). Intubation through the ILMA was successful in 159 of 192 patients (83%), including a success rate of 81% (112 of 139 patients) with blind intubation.

Conclusion: The ILMA was highly successful in oxygenation, with reasonable intubation success, even when used infrequently by emergency physicians. The ILMA should be considered a valuable primary and rescue intubation device in the ED.

Prehospital Mortality Due to Hemorrhagic Shock Remains High and Unchanged: A Summary of Current Civilian EMS Practices and New Military Changes

Juan Duchesne, Sharven Taghavi, August Houghton, Mansoor Khan, Bruno Perreira, Bryan Cotton, Danielle Tatum, Megan Brenner, Paula Ferrada, Tal Horer, David Kauvar, Andrew Kirkpatrick, Carlos Ordonez, Artai Priouzram, Derek Roberts, Damage Control Resuscitation Committee

Shock 2020 Feb 19; Online ahead of print 

Abstract

Mortality secondary to trauma related hemorrhagic shock has not improved for several decades. Underlying the stall in progress is the conundrum of effective pre-hospital interventions for hemorrhage control. As we know, neither pressing hard on the gas nor "Stay and play" have changed mortality over the last 20 years. For this reason, when dealing with effective changes that will improve severe hemorrhage mortality outcomes, there is a need for the creation of a hybrid pre-hospital model. Improvements in mortality outcomes for patients with severe hemorrhage based on evidence for common civilian prehospital procedures such as in-field intubation and immediate fluid resuscitation with crystalloid solution is weak at best. The use of tourniquets, once considered too risky to use, however, has risen dramatically in large part due success seen during their use in the military. Their use in the civilian setting shows promising results. Recently updated military Advanced Resuscitative Care (ARC) guidelines propose the use of prehospital whole blood transfusion as well as in-field use of Zone 1 Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA). Several case studies from Europe suggest these strategies are feasible for use in the civilian population, but could they be implemented in the U.S.?

Point-of-care ultrasound at Role 1: is it time for a rethink?

Patrick G A Duncan, J Mackey

BMJ Mil Health 2020 May 20;Online ahead of print 

Introduction: The past 20 years have seen a rapid increase in point-of-care ultrasound (POCUS) use in the prehospital sphere. However, in the British Army there is no POCUS capability in the Defence Primary Healthcare (DPHC) or deployed Role 1 setting. POCUS can improve diagnostic capability, influence management decisions and transfer destination, and is a useful triage tool in mass casualty management.

Method: A survey on POCUS use was sent to 279 clinicians working in the Role 1, civilian prehospital and Defence Primary Healthcare environments. Questions explored current levels of experience and training, indications for use and attitudes towards roll out. Results were analysed using a mixed methods approach.

Results: There were 124 respondents (279 recipients; 44.4% response rate). 74.2% (92 respondents) had no experience of using POCUS while 9.7% (12 respondents) were classed as frequent users. The four most common indications for prehospital POCUS were abdominal, cardiac and lung imaging and vascular access. The majority of respondents felt that POCUS would add value in the deployed Role 1 environment; this was even more evident in the frequent user group. Common concerns were difficulty maintaining currency, governance burden and uncertainty over impact on management.

Conclusion: The majority of doctors surveyed feel that POCUS would add value at Role 1 and is a capability that should be developed. The authors will watch with interest the progress of Project MORPHO.

Traumatic injury results in prolonged circulation of ultralarge von Willebrand factor and a reduction in ADAMTS13 activity

Mitchell R Dyer, William E Plautz, Margaret V Ragni, Wyeth Alexander, Shannon Haldeman, Jason L Sperry, Francis X Guyette, Brian S Zuckerbraun, Marian A Rollins- Raval, Jay S Raval, Matthew D Neal, A TACTIC Publication

Transfusion 2020 Jun;60(6):1308-1318 

Background: Increases in plasma von Willebrand Factor (VWF) levels, accompanied by decreases in the metalloprotease ADAMTS13, have been demonstrated soon after traumatic injury while downstream effects remain unclear.

Study design and methods: A cohort of 37 injured trauma patients from a randomized control trial investigating the use of prehospital plasma transfusion were analyzed for activity and antigen levels of ADAMTS13 and VWF at 0 and 24 hours after admission. Relevant clinical data were abstracted from the medical records. Trauma patient plasma was analyzed via agarose gel electrophoresis to evaluate the effects of injury on VWF multimer composition compared to healthy controls.

Results: von Willebrand factor levels were elevated at presentation (189% [110%-263%] vs. 95% [74%-120%]), persisting through 24 hours (213% [146%-257%] vs. 132% [57%-160%]), compared to healthy controls. Ultralarge VWF (UL-VWF) forms were elevated in trauma patients at both 0 and 24 hours, when compared to pooled normal plasma (10.0% [8.9%-14.3%] and 11.3% [9.1%-21.2%], respectively, vs. 0.6%). Circulating plasma ADAMTS13 activity was decreased at 0 hours (66% [47%-86%] vs. 100% [98%-100%]) and at 24 hours (72.5% [56%- 87.3%] vs. 103% [103%-103%]) in trauma patients. ADAMTS13 activity independently predicted the development of coagulopathy and correlated with international normalized ratio, thromboelastography values, injury severity, and blood product transfusion.

Conclusion: Traumatic injury is associated with acute coagulopathy that is characterized by increased UL-VWF multimers and reduction in ADAMTS13, which correlates with blood loss, transfusion requirement, and injury severity. These findings suggest the potential for future trials targeting ADAMTS13 repletion to enhance clearance of VWF multimers.

Association of Risk of Mortality in Pediatric Patients Transferred From Scene by Helicopter With Major But Not Minor Injuries

Ali Duffens, Areg Grigorian, Christian de Virgilio, Theresa Chin, Dennis Kim, Michael Lekawa, Sebastian D Schubl, Jeffry Nahmias

Pediatr Emerg Care. 2020 Oct 22. doi: 10.1097/PEC.0000000000002263. Online ahead of print. 

Objectives: Helicopter emergency medical services (HEMS) are used for 16% of pediatric trauma. National HEMS guidelines advised that triage criteria be standardized for pediatric patients. A national report found pediatric HEMS associated with decreased mortality compared with ground emergency medical services (GEMS) but did not control for transport time. We hypothesized that the rate of HEMS has decreased nationally and the mortality risk for HEMS to be similar when adjusting for transport time compared with GEMS.

Methods: The Pediatric Trauma Quality Improvement Program (2014-2016) was queried for patients younger than 16 years transported by HEMS or GEMS. A multivariable logistic regression was used.

Results: From 25,647 patients, 4527 (17.7%) underwent HEMS. The rate of HEMS from scene decreased from 21.2% in 2014 to 18.2% in 2016. The rate of HEMS for minor trauma (Injury Severity Score <15) decreased from 14.9% in 2014 to 13.5% in 2016 and major trauma (Injury Severity Score > 15) from 38.4% in 2014 to 35.9% in 2016. After controlling for predictors of mortality and transport time, HEMS was associated with decreased risk of mortality for only those with major injuries transferred from scene (odds ratio, 0.48; 95% confidence interval, 0.26-0.88; P = 0.01) compared with GEMS.

Conclusions: The rate of HEMS in pediatric trauma has decreased. However, there is room for improvement as 14% of those with minor trauma are transported by HEMS. Given the similar risk of mortality compared with GEMS, further development of guidelines that avoid the unnecessary use of HEMS appears warranted. However, utilization of HEMS for transport of pediatric major trauma should continue.

Airway Management in Prolonged Field Care

Collin Dye, Sean Keenan, Brandon M Carius, Paul E Loos, Michael A Remley, Brandon Mendes, Jacob L Arnold, Ian May, Douglas Powell, Joshua M Tobin, Jamie C Riesberg, Stacy A Shackelford

J Spec Oper Med. Fall 2020;20(3):141-156. 

This Role 1, prolonged field care (PFC) clinical practice guideline (CPG) is intended to be used after Tactical Combat Casualty Care (TCCC) Guidelines, when evacuation to higher level of care is not immediately possible. A provider must first and foremost be an expert in TCCC, the Department of Defense standard of care for first responders. The intent of this PFC CPG is to provide evidence and experience-based solutions to those who manage airways in an austere environment. An emphasis is placed on utilizing the tools and adjuncts most familiar to a Role 1 provider. The PFC capability of airway is addressed to reflect the reality of managing an airway in a Role 1 resource-constrained environment. A separate Joint Trauma System CPG will address mechanical ventilation. This PFC CPG also introduces an acronym to assist providers and their teams in preparing for advanced procedures, to include airway management.

To intubate or not to intubate? Predictors of inhalation injury in burn-injured patients before arrival at the burn centre

Kylie Dyson, Paul Baker, Nicole Garcia, Anna Braun, Myat Aung, David Pilcher, Karen Smith, Heather Cleland, Belinda Gabbe

Emerg Med Australas . 2021 Apr;33(2):262-269 

Objective: Inhalation injury occurs in approximately 10-20% of burn patients and is associated with increased mortality. There is no clear method of identifying patients at risk of inhalation injury or requiring intubation in the pre-hospital setting. Our objective was to identify pre-burn centre factors associated with inhalation injury confirmed on bronchoscopy, and to develop a prognostic model for inhalation injury.

Methods: We analysed acute admissions from the Victorian Adult Burns Service and Ambulance Victoria electronic patient care records for 1 July 2009 to 30 June 2016. We defined inhalation injury as an Abbreviated Injury Scale of >1 on bronchoscopy. A multivariable logistic regression prediction model was developed based on pre-burn centre factors.

Results: Emergency medical services transported 1148 patients who were admitted to the burn centre. The median age of patients was 39 years and most patients had <10% total body surface area (%TBSA) burned. The prevalence of confirmed inhalation injury was 11%. Increasing %TBSA burned, flame, enclosed space, face burns, hoarse voice, soot in mouth and shortness of breath were predictive of inhalation injury. The model provided excellent discrimination (area under curve 0.87, 95% confidence interval 0.84-0.91). A lower proportion of patients intubated at a non-burn centre had an inhalation injury (33%) compared to patients intubated by emergency medical services (54%) and in the burn centre (58%).

Conclusions: A model to predict inhalation injury in burn-injured patients was developed with excellent discrimination. This model requires prospective testing but could form an integral part of clinician decision-making.

Canine Tactical Combat Casualty Care (K9TCCC) Guidelines

Thomas H Edwards, Lee E Palmer, Rebecca L Baxter, Thomas C Sager, James G Coisman, Jamie C Brown, Clinton George, Andrew C McGraw

J Spec Oper Med Spring 2020;20(1):101-111. 

First introduced in 1996, Tactical Combat Casualty Care (TCCC) redefined prehospital, point-of- injury (POI), battlefield trauma care for the human combat casualty. Today, many consider TCCC as one of the most influential interventions for reducing combat-related case fatality rates from preventable deaths in human combat casualties. Throughout history, Military Working Dogs (MWDs) have proved and continue to prove themselves as force multipliers in the success of many military operations. Since the start of the Global War on Terror in 2001, these elite canine operators have experienced an upsurge in combat-related deployments, placing them at a higher risk for combat-related injuries. Until recently, consensus- based Canine-TCCC (K9TCCC) guidelines for POI battlefield trauma care did not exist for the MWD, leaving a critical knowledge gap significantly jeopardizing MWD survival. In 2019, the Canine Combat Casualty Care Committee was formed as an affiliate of the Committee on Tactical Combat Casualty Care with the intent of developing evidence- based, best practice K9TCCC guidelines. Modeled after the same principles of the human TCCC, K9TCCC focuses on simple, evidence-based, field- proven medical interventions to eliminate preventable deaths and to improve MWD survival.  

Customized for the battlefield, K9TCCC uniquely adapts the techniques of TCCC to compensate for canine-specific anatomic and physiological differences.

Superficial Stab Wound to Zone I of the Neck Resulting in Thyrocervical Trunk Pseudoaneurysm Presented as Recurrent Hemothorax and Successfully Managed by Coil Embolization

Adel Elkbuli, Saamia Shaikh, John D Ehrhardt Jr, Mark McKenney, Dessy Boneva.

Am J Case Rep 2020 Mar 8;21:e920196 

BACKGROUND Thyrocervical trunk pseudoaneurysms are rare complications that have been documented after internal jugular or subclavian venous cannulation. Even less common, these pseudoaneurysms can arise after blunt or penetrating trauma. Clinical hallmarks include an expanding supraclavicular mass with local compressive symptoms such as paresthesias, arterial steal syndrome, and Horner's syndrome. Patients may be asymptomatic, however, or present with overlying ecchymosis or the presence of a new bruit or thrill. With the risk of rupture, thyrocervical trunk pseudoaneurysm is associated with significant morbidity and mortality. CASE REPORT We report the case of a 27-year-old man who presented after sustaining a self-inflicted stab wound to zone I of his neck. Initial examination revealed only a superficial small laceration, but a chest x-ray revealed a pneumothorax, and tube thoracostomy returned 300 mL of bloody output. After resolution of the hemothorax and removal of the thoracostomy tube, the patient reaccumulated blood, requiring a repeat tube thoracostomy.

Angiography at that time revealed a pseudoaneurysm of the thyrocervical trunk, and coil embolization was performed to obliterate the pseudoaneurysm. CONCLUSIONS Thyrocervical trunk pseudoaneurysms can be asymptomatic, often have a delayed presentation, and can be life-threatening due to the risk of rupture and subsequent hemodynamic decline or airway compromise. While these pseudoaneurysms are well-known complications of deep penetrating injuries, they can also present following superficial penetrating injury to zone I of the neck.

Selective angiography is the imaging modality of choice. Open surgical repair was traditionally the criterion standard for treatment; however, endovascular approaches are minimally invasive, feasible, and safer alternatives with reduced complications and are becoming more common.

Assessment of firearm injuries undergoing advanced airway management: Role II hospital experience 

Sami Eksert, Mehmet Burak Asik, Murtaza Kaya 

Ulus Travma Acil Cerrahi Derg. 2020 Mar;26(2):301-305 

Background: Airway problems are one of the most important factors affecting mortality in firearm injuries. The present study aims to examine the data of patients who underwent advanced airway support due to explosion and bullet injuries in a Role II hospital. 

Methods: Ninety three patients who underwent advanced airway support due to gunshot wounds in a Role II hospital between January 2015 and September 2016 were included in this study. The patients were divided into two groups as blast (Group A) (handmade explosives, rocket, and mine) and bullet (Group B) (rifle and pistol bullet) trauma injuries. The groups were compared regarding pre-hospital intubation, NISS (New Injury Severity Score), cardio-pulmonary resuscitation (CPR), emergency surgical intervention and mortality rates. 

Results: There was no difference between the patient groups concerning demographic and clinical features. Thirty-six patients were included in group A, and 57 patients were included in group B. There was no statistically significant difference between the groups about emergency surgical intervention rates (p=0.42). However, a statistically significant difference was observed between the groups in terms of pre-hospital intubation (p=0.001), CPR application (p=0.001), mortality (p=0.001) rates and NISS (p=0.002) scores. 

Conclusion: Bullet injuries that require advanced airway are more destructive and more deadly than explosion injuries. This may be due to direct airway or organ damage in bullet gunshot wounds.

A rare case of pre-hospital globe enucleation after a penetrating injury to the orbit during an assault: A case report and literature review 

Adel Elkbuli, Evander Meneses, Kyle Kinslow, Mark McKenney, Dessy Boneva 

Int J Surg Case Rep. 2020;75:231-234 

Introduction: Ocular trauma is a common occurrence in trauma settings but often occurs with little to no effect on the vision of the patient. Traumatic enucleation is a rare but devastating injury. 

Case presentation: A 40-year-old male presented to our trauma center after an assault resulting in right globe enucleation. CT confirmed absence of the globe with disruption of the ipsilateral orbital contents and distal optic nerve disruption. The patient was started on intravenous antibiotics and the right orbit was packed. He was taken to the operating room for exploration of the right orbit and placement of an implant. His remaining hospital course was unremarkable. 

Discussion: Documented mechanisms of injury for traumatic enucleation are diverse, but often involve significant retro-ocular force to completely dislodge the globe from the orbit. Optic nerve avulsion may cause associated optic nerve chiasm damage leading to temporal hemianopia in the uninjured contralateral eye. Treatment involves stabilization and preparation for future implant placement. 

Conclusion: Traumatic enucleation is extremely rare. Development of a grading system applicable to traumatic enucleation may be helpful in guiding management in this complex patient population. 

Keywords: Assault; Optic chiasm injuries; Optic nerve avulsion; Temporal hemianopia; Traumatic enucleation.

 

The Efficacy of Novel Commercial Tourniquet Designs for Extremity Hemorrhage Control: Implications for Spontaneous Responder Every Day Carry 

Joshua Ellis, Melissa M Morrow, Alec Belau, Luke S Sztajnkrycer, Jeffrey N Wood, Tobias Kummer, Matthew D Sztajnkrycer

Prehosp Disaster Med 2020 Jun;35(3):276-280 

Introduction: Tourniquets (TQs) save lives. Although military-approved TQs appear more effective than improvised TQs in controlling exsanguinating extremity hemorrhage, their bulk may preclude every day carry (EDC) by civilian lay-providers, limiting availability during emergencies.

Study objective: The purpose of the current study was to compare the efficacy of three novel commercial TQ designs to a military-approved TQ.

Methods: Nine Emergency Medicine residents evaluated four different TQ designs: Gen 7 Combat Application Tourniquet (CAT7; control), Stretch Wrap and Tuck Tourniquet (SWAT-T), Gen 2 Rapid Application Tourniquet System (RATS), and Tourni-Key (TK). Popliteal artery flow cessation was determined using a ZONARE ZS3 ultrasound. Steady state maximal generated force was measured for 30 seconds with a thin-film force sensor.

Results: Success rates for distal arterial flow cessation were 89% CAT7; 67% SWAT-T; 89% RATS; and 78% TK (H 0.89; P = .83). Mean (SD) application times were 10.4 (SD = 1.7) seconds CAT7; 23.1 (SD = 9.0) seconds SWAT-T; 11.1 (SD = 3.8) seconds RATS; and 20.0 (SD = 7.1) seconds TK (F 9.71; P <.001). Steady state maximal forces were 29.9 (SD = 1.2) N CAT7; 23.4 (SD = 0.8) N SWAT-T; 33.0 (SD = 1.3) N RATS; and 41.9 (SD = 1.3) N TK.

Conclusion: All novel TQ systems were non-inferior to the military-approved CAT7. Mean application times were less than 30 seconds for all four designs. The size of these novel TQs may make them more conducive to lay-provider EDC, thereby increasing community resiliency and improving the response to high-threat events.

Endotracheal tube fixation time: a comparison of three fixation methods in a military field scenario

Danny Epstein, R Strashewsky A Furer, A M Tsur, J Chen, A Lehavi BMJ Mil Health 2020 Mar 23;bmjmilitary-2020-001402. 

Introduction: Endotracheal intubation is required in many emergency, trauma and prehospital scenarios. Endotracheal tube (ETT) fixation must be stable and quick to apply to enable rapid evacuation and patient transport. This study compares performance times of three common ETT securement techniques which are practical for out-of-hospital and combat scenarios.

Methods: We compared the time required by military medics to complete ETT fixation in three techniques-fixation of a wide gauze roll wrapped twice around the head and tied twice around the ETT (GR), using a Thomas Tube Holder (TH) and using a pre-tied non-adhesive tape (PT). 300 military medics were randomised to apply one technique each on a manikin, and time to completion was recorded.

Results: 300 ETTs were successfully fixated by 300 military medics. Median times to complete ETT fixation by PT and TH techniques were 24 s (IQR (19 to 31) and (IQR 20 to 33), respectively). Both were significantly shorter to apply than the GR technique, with a median time of 57 s (IQR 47 to 81), p<0.001.

Conclusions: In time critical situations such as combat, severe trauma, mass casualties and whenever rapid evacuation might improve the clinical outcome, using a faster fixation technique such as Thomas Tube Holder or a pre-tied non-adhesive tape might enable faster evacuation than the use of traditional endotracheal tube fixation techniques.

Traumatic Brain Injuries: Unreported and Untreated in an Army Population Sandra M Escolas, Margie Luton, Hamid Ferdosi, Bianca D Chavez, Scot D Engel

Mil Med 2020 Jan 7;185(Suppl 1):154-160 

Abstract

Introduction: In 2008, it was reported that 19.5% of service members previously deployed experienced a mild traumatic brain injury (mTBI). Fifty-seven percent of those did not seek medical care. It was suggested that concerns with seeking care involved confidentiality and career issues. Objective: This study addressed mTBI history, medical treatment history, and stigmas associated with mTBI/concussion.

Materials and methods: An anonymous questionnaire was developed. Data collection occurred throughout March 2018 in conjunction with Brain Injury Awareness Month activities.

Results: All 5,174 volunteers were Army; 86% male; 87% were between 18 and 34 years old; 89% had <14 years in the military; 35% had a combat deployment; and 10% reported having one or more mTBIs in their military careers. Of the Soldiers who reported a concussion, 52% sought medical care. Of those not seeking care, 64% reported they did not think the injury required care, followed by 18% fearing negative impact on their career. Twenty-eight percent who experienced an mTBI versus 11% who have not reported that there is a stigma associated with an mTBI.

Conclusions: Soldiers sometimes failed to report their suspected concussions and did not seek medical care. Educational efforts may increase reporting of and medical screening for potentially concussive events. Future research to determine the ramifications of unreported and untreated mTBIs/concussions is recommended.

Traumatic Brain Injuries: Unreported and Untreated in an Army Population

Sandra M Escolas, Margie Luton, Hamid Ferdosi, Bianca D Chavez, Scot D Engel

Mil Med 2020 Jan 7;185(Suppl 1):154-160 

Abstract

Introduction: In 2008, it was reported that 19.5% of service members previously deployed experienced a mild traumatic brain injury (mTBI). Fifty-seven percent of those did not seek medical care. It was suggested that concerns with seeking care involved confidentiality and career issues. Objective: This study addressed mTBI history, medical treatment history, and stigmas associated with mTBI/concussion.

Materials and methods: An anonymous questionnaire was developed. Data collection occurred throughout March 2018 in conjunction with Brain Injury Awareness Month activities.

Results: All 5,174 volunteers were Army; 86% male; 87% were between 18 and 34 years old; 89% had <14 years in the military; 35% had a combat deployment; and 10% reported having one or more mTBIs in their military careers. Of the Soldiers who reported a concussion, 52% sought medical care. Of those not seeking care, 64% reported they did not think the injury required care, followed by 18% fearing negative impact on their career. Twenty-eight percent who experienced an mTBI versus 11% who have not reported that there is a stigma associated with an mTBI.

Conclusions: Soldiers sometimes failed to report their suspected concussions and did not seek medical care. Educational efforts may increase reporting of and medical screening for potentially concussive events. Future research to determine the ramifications of unreported and untreated mTBIs/concussions is recommended.

Best Practices for Progressive Return to Activity after Concussion: Lessons Learned from a Prospective Study of U.S. Military Service Members 

Mark L Ettenhofer, Rosemay A Remigio-Baker, Jason M Bailie, Wesley R Cole, Emma Gregory 

Neurotrauma Rep. 2020 Oct 29;1(1):137-145 

Abstract 

Primary care providers can play a crucial role in the clinical management of concussion. However, many providers lack up-to-date information about best practices for rest and return to activity after these injuries. Most research on this topic has been conducted in athletes, and so less is known about how to assist patients with returning to activity in other settings and populations. This article provides a review of best practices for management of progressive return to activity after concussion, with an emphasis on "lessons learned" from the Defense and Veterans Brain Injury Center (DVBIC) Progressive Return to Activity (PRA) study, a multi-site longitudinal research project conducted to evaluate concussion management practices and the effectiveness of provider training on DVBIC clinical recommendations (CRs). Provider clinical practices and patient outcomes were examined at three U.S. military treatment facilities before and after providers completed a standardized training on DVBIC PRA CRs. In summary, research findings provide additional support that concussion recovery can be influenced by patients' activity levels after injury. Patients with concussion may experience poorer outcomes if they return to pre-injury levels of activity too rapidly, but they may also be at risk for prolonged symptoms if they fail to increase activity levels over time after an initial period of rest. Additionally, training primary care providers in return to activity guidelines can result in more effective patient education and better clinical outcomes. This knowledge can be used to inform best practices for progressive return to activity in both civilian and military settings.

Is fascia iliaca compartment block administered by paramedics for suspected hip fracture acceptable to patients? A qualitative study

Bridie Angela Evans, Alan Brown, Greg Fegan, Simon Ford, Katy Guy, Jenna Jones, Sian Jones, Leigh Keen, Ashrafunnesa Khanom, Mirella Longo, Ian Pallister, Nigel Rees, Ian T Russell, Anne C Seagrove, Alan Watkins, Helen Snooks

BMJ Open 2019 Dec 19;9(12):e033398 

Abstract

Objective: To explore patients' experience of receiving pain relief injection for suspected hip fracture from paramedics at the location of the injury.

Design: Qualitative interviews within a feasibility trial about an alternative to routine prehospital pain management for patients with suspected hip fracture.

Setting: Patients treated by paramedics in the catchment area of one emergency department in South Wales.

Participants: Six patients and one carer of a patient who received fascia iliaca compartment block (FICB).

Intervention: FICB administered to patients with suspected hip fracture by trained paramedics. We randomly allocated eligible patients to FICB-a local anaesthetic injection directly into the hip region-or usual care-most commonly morphine-using audited scratch cards.

Outcomes: Acceptability and experience of receiving FICB, assessed through interview data. We audio-recorded, with participants' consent, and conducted thematic analysis of interview transcripts. The analysis team comprised two researchers, one paramedic and one lay member.

Results: Patients had little or no memory of being offered, consenting to or receiving FICB. They recalled the reassuring manner and high quality of care received. They accepted FICB without question. Partial or confused memory characterised experience of subsequent hospital care until surgery. They said their priorities when calling for emergency help were to receive effective care. After hospital treatment, they wanted to regain their health and mobility and resume the quality of life they experienced before their injury.

Conclusions: This study did not raise any concerns about the acceptability of FICB administered at the scene of injury by paramedics to people with suspected hip fracture. It adds to existing evidence about patient and carer experience of on-scene care for people with suspected hip fracture. Further research is needed to assess safety, effectiveness and cost effectiveness of this health technology in a new setting.

Aeromedical evacuation: experiences from the UK military level 2 hospital in Bentiu, South Sudan, during Op TRENTON

Leanne Jane Eveson, W Nevin, N Cordingley, M Almond BMJ Mil Health 2020 Apr 27;bmjmilitary-2020-001448 

Introduction: Aeromedical Evacuation (AE) is a vital role of the Defence Medical Services (DMS). With a far-reaching defence global footprint, an AE capability is crucial to enable movement of patients in the fastest, safest and least stressful way that meets or exceeds the level of care an injured or ill person may expect to receive in the UK. Operation (Op) TRENTON is a UK military humanitarian operation in support of the United Nations (UN) Mission in South Sudan.

Methods: A retrospective analysis was carried out of all patients who underwent AE from the UK level 2 hospital at Bentiu during Op TRENTON over a 17-month period from June 2017 to October 2018.

Results: 14 patients underwent AE. The median age was 36 (22-64) years and all patients were male. 21% of AEs were for UK personnel and 79% were for UN personnel. 29% of AEs were due to non-battle injury with the remainder due to disease. Musculoskeletal was the largest diagnostic group (n=4) followed by respiratory (n=3), cardiovascular (n=2), undifferentiated febrile illness (n=2), neurology (n=1), renal medicine (n=1) and psychiatry (n=1).

Conclusions: Patients requiring AE from the level 2 hospital at Bentiu mostly had musculoskeletal and medical pathology, a stark contrast to the trauma patient cohort from operations in the past. The majority of patients had definitive care under the medical team highlighting the requirement for DMS physicians and the AE team, to be trained in acute, general and aviation medicine. The majority of AE moves were for UN personnel and on UN airframes, highlighting the importance of a sound understanding of the nations we are working with.

Rapid hemostatic chitosan/cellulose composite sponge by alkali/urea method for massive haemorrhage 

Xialian Fan, Yijin Li, Na Li, Guangming Wan, Muhammad Amir Ali, Keyong Tang 

Int J Biol Macromol. 2020 Dec 1;164:2769-2778 

Abstract 

Here, a simple and efficient strategy to produce porous and hydrophilic chitosan/cellulose sponge using surfactant and pore-forming agent is demonstrated. The preparation of composite sponge by LiOH/KOH/urea solvent system effectively solve the problems of uneven distribution of chitosan, poor softness and acid residue caused by soaking in chitosan acid solution. The obtained chitosan/cellulose sponges exhibit high water absorption capacity and rapid shape recoverability, as well as good mechanical properties. Effective inhibitory on Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa are particularly proved. Besides, the result of the dynamic whole blood clotting time indicated that the chitosan/cellulose composite sponge has better coagulation ability than those of traditional gauze and gelatin sponge. Animal experiment further showed that rapid hemostasis within 34 s can be reached with the composite sponge. Better biocompatibility of the composite sponge is proved by the results of hemocompatibility and cytotoxicity, indicating an excellent candidate for rapid hemostasis in massive haemorrhage.

Freeze-dried plasma in major haemorrhage: a systematic review

Solveig Johanna Feuerstein, Kamilla Skovmand, Ann Merete Møller, Kim Wildgaard Vox Sang 2020 May;115(4):263-274 

Background and objectives: Freeze-dried plasma (FDP) has logistical advantages in terms of storage and reconstitution time compared to fresh-frozen plasma. In vitro studies show FDP to be equivalent to fresh-frozen plasma regarding coagulation and clotting capacities. FDP is used in an increasing number of countries. We wanted to evaluate the clinical effects of FDP in major haemorrhage compared to standard care.

Methods: MEDLINE, Embase, Central, Biosis Previews, WHO ICTRP, Clinical Trials and Open Grey were systematically searched from inception until September 2018, without language restriction. Studies were eligible if they examined haemorrhagic adult patients transfused with FDP. Our primary outcome was mortality. Two reviewers independently assessed studies for eligibility, extracted data and assessed bias.

Results: Nine studies were eligible for inclusion. Three studies had a comparison group: one was a randomized controlled trial and two were before and after comparisons. Six studies were uncontrolled. A total of 606 patients received FDP, while 72 patients received non-FDP transfusion. In total, five minor adverse effects were documented. Two studies compared FDP to fresh-frozen plasma and found no difference in 30-day mortality between the groups. The included studies were heterogenous and had several methodological weaknesses, such as no control group, missing data or no protocol.

Conclusions: The available research does not document the clinical effects of FDP. We cannot recommend or discourage use of FDP in major haemorrhage on base of available research.

Evaluation of Different Positive End-Expiratory Pressures Using Supreme™ Airway Laryngeal Mask during Minor Surgical Procedures in Children

Mascha O Fiedler, Elisabeth Schätzle, Marius Contzen, Christian Gernoth, Christel Weiß, Thomas Walter, Tim Viergutz, Armin Kalenka

Medicina (Kaunas). 2020 Oct 21;56(10):551 

Background and objectives: The laryngeal mask is the method of choice for airway management in children during minor surgical procedures. There is a paucity of data regarding optimal management of mechanical ventilation in these patients. The Supreme™ airway laryngeal mask offers the option to insert a gastric tube to empty the stomach contents of air and/or gastric juice. The aim of this investigation was to evaluate the impact of positive end-expiratory positive pressure (PEEP) levels on ventilation parameters and gastric air insufflation during general anesthesia in children using pressure-controlled ventilation with laryngeal mask. Materials and Methods: An observational trial was carried out in 67 children aged between 1 and 11 years. PEEP levels of 0, 3 and 5 mbar were tested for 5 min in each patient during surgery and compared with ventilation parameters (dynamic compliance (mL/cmH2O), etCO2 (mmHg), peak pressure (mbar), tidal volume (mL), respiratory rate (per minute), FiO2 and gastric air (mL)) were measured at each PEEP. Air was aspirated from the stomach at the start of the sequence of measurements and at the end. Results: Significant differences were observed for the ventilation parameters: dynamic compliance (PEEP 5 vs. PEEP 3: p < 0.0001, PEEP 5 vs. PEEP 0: p < 0.0001, PEEP 3 vs. PEEP 0: p < 0.0001), peak pressure (PEEP 5 vs. PEEP 3: p < 0.0001, PEEP 5 vs. PEEP 0: p < 0.0001, PEEP 3 vs. PEEP 0: p < 0.0001) and tidal volume (PEEP 5 vs. PEEP 3: p = 0.0048, PEEP 5 vs. PEEP 0: p < 0.0001, PEEP 3 vs. PEEP 0: p < 0.0001). All parameters increased significantly with higher PEEP, with the exception of etCO2 (significant decrease) and respiratory rate (no significant difference). We also showed different values for air quantity in the comparisons between the different PEEP levels (PEEP 5: 2.8 ± 3.9 mL, PEEP 3: 1.8 ± 3.0 mL; PEEP 0: 1.6 ± 2.3 mL) with significant differences between PEEP 5 and PEEP 3 (p = 0.0269) and PEEP 5 and PEEP 0 (p = 0.0209). Conclusions: Our data suggest that ventilation with a PEEP of 5 mbar might be more lung protective in children using the Supreme™ airway laryngeal mask, although gastric air insufflation increased with higher PEEP. We recommend the use of a laryngeal mask with the option of inserting a gastric tube to evacuate potential gastric air.

The Role of Tranexamic Acid (TXA) in Military Trauma: Current Practices and Implications for the Future

Hugh W Finlayson

Traumatology (Tallahass Fla) 2018;0:2018. 

Objectives: To review current literature on the use of Tranexamic acid in battlefield trauma to assess its effects on mortality and determine whether or not it should become more widely used in both civilian and military trauma.A subsection was to look at the feasibility of administering Tranexamic acid in a pre-hospital setting to minimise the time between injury and drug administration.

Methods: A search of the literature was performed on a variety of databases using the terms described in table 1. The papers were then reviewed and analysed regarding the effects of the drug in trauma.

Patients: The papers selected reviewed 21,160 patients as detailed in Table 2. These patients were across both military and civilian trauma units.

Outcomes: The main outcomes being examined were the effects on short term mortality at 24 and 48 hours and whether there was any increase in the thromboembolic risk associated with the administration of Tranexamic acid.

Results: The review of the literature showed that Tranexamic acid had a significant effect on improving mortality across the board (17.4% vs 23.9% mortality (p = 0.03)). This was most marked in the more severely injured who had received over 10 units of transfused blood (14.4% vs 28.4% mortality (p = 0.004)).In terms of side effects Tranexamic acid was shown to be safe in large doses, which is key for battlefield administration where there is a tendency to err on the side of overtreating. Interestingly, the risk of thromboembolic events was similar to those not receiving Tranexamic acid.

Conclusions: Tranexamic acid is a very safe and effective means of improving survival when used in combination with current practices involving the use of blood products and surgical interventions. Tranexamic acid can safely be administered in the pre-hospital setting to minimise the delay between injury and treatment. The use of Tranexamic acid should be incorporated into trauma management across the board in the both military and civilian cases particularly in the most severe cases.

Implementation of a low titer group O whole blood program for a law enforcement tactical team

Andrew D Fisher, John Dunn, Jason R Pickett, Justine Garza, Ethan A Miles, Vivian Diep, Mark Escott

Transfusion 2020 Jun;60 Suppl 3:S36-S44 

The Texas Ranger Special Operations Group (SOG) performs high-risk warrant service and responds to callouts for evolving kinetic situations and special missions as required. These operations may occur many hours from a trauma center. Fresh whole blood (FWB) transfusions may offer a stopgap for those who are critically injured. To make FWB transfusions a viable option, several steps must be implemented. The following lays out how the Texas Ranger SOG will implement and conduct FWB transfusions using low titer group O whole blood. The techniques outlined may be useful for communities that may face critical blood shortage in disasters.

Slow and Risky to Safe and Briskly: Modern Implementation of Whole Blood

Andrew D Fisher, Ethan A Miles, Stacy Shackelford

J Spec Oper Med Spring 2020;20(1):21-25. 

Saving lives on the battlefield goes beyond eliminating what is currently considered preventable deaths and encompasses the treatment of potentially survivable injuries. Eliminating potentially preventable deaths is a driving force for identifying and implementing advanced treatment strategies. Potentially survivable injuries present a difficult challenge to the combat medic, because noncompressible torso hemorrhage (NCTH) can be particularly complex to treat.

Without timely surgical care, many casualties in the potentially survivable category will die because immediate evacuation is not always possible. Therefore, the focus of training and treatment should be on eliminating preventable death and the management of potentially survivable injuries through damage control resuscitation (DCR) and advancing treatment for NCTH.

The lessons learned from prior wars continue to be relevant as we adapt them to today’s conflicts. We must seek evolving technological material solutions as well as techniques from the past and future to save lives. As the TCCC community, we must not forget to continue to master the basics and eliminate preventable death while we push on toward saving the potentially survivable.

Prehospital Vasopressor Use Is Associated with Worse Mortality in Combat Wounded

Andrew D Fisher, Michael D April, Cord Cunningham, Steven G Schauer

Prehosp Emerg Care 2020 Mar 20;1-6 

Abstract

Introduction: Vasopressor medications are frequently used in the management of hypotension secondary to shock. However, little data exists regarding their use in hypotensive trauma patients and their use is controversial.

Methods: The Department of Defense Trauma Registry was queried from January 2007 to August 2016 using a series of procedural codes to identify eligible casualties, which has been previously described. Mortality was compared between hypotensive casualties with documentation of receipt of vasopressor medications versus casualties not receiving vasopressors. To control for potential confounders, comparisons were repeated by constructing a multivariable logistic regression model that utilized patient category, mechanism of injury, composite injury severity score, total blood products transfused, prehospital heart rate and prehospital systolic pressure. Survival was compared between these groups using propensity matching.

Results: Our search strategy yielded 28,222 patients, 124 (0.4%) of whom received prehospital vasopressors. On univariable analysis vasopressor use was associated with lower odds of survival (OR 0.09, 0.06-0.13). The lower odds of survival persisted in the multivariate logistic regression model (OR 0.32, 0.18-0.56). Survival was lower among the vasopressor group (71.3%) when compared to a propensity matched cohort (94.3%).

Conclusions: In this dataset, prehospital vasopressor use was associated with lower odds of survival. This finding persisted when adjusting for confounders and in a propensity matched cohort model.

An analysis of the incidence of hypothermia in casualties presenting to emergency departments in Iraq and Afghanistan

Andrew D Fisher, Michael D April, Steven G Schauer

Am J Emerg Med 2019 Dec 9;S0735-6757(19)30792-2 

Introduction: Hypothermia on the battlefield has been shown to be associated with severe injury and higher mortality. The incidence of battlefield casualties presenting with hypothermia are described.

Methods: The Department of Defense Trauma Registry (DoDTR) was queried from January 2007 to August 2016. We identified casualties with a documented temperature of <32°Celsius(C) (severe), 32-33.9 °C (moderate), 34-36 °C (mild). We defined serious injuries as those resulting in an AIS of ≥3 by body region.

Results: There were 25,484 records with at least one documented temperature and 2501 (9.8%) casualties with hypothermia within our range. Nineteen (0.75%) casualties presented with severe hypothermia, 225 (9%) with moderate, and 2257 (90%) with mild. The mean injury severity score (ISS) for non-hypothermic, mild, moderate, and severe hypothermic casualties was 8 [4-14], 14 [6-24], 21 [13-29], and 21 [9-25], (p <0.001), respectively. Survival for casualties with severe hypothermia was 57.8%, moderate 80.9%, mild hypothermia 90.9%, and non-hypothermic group 97.6%, p<0.001. When adjusting for composite injury score, patient category, mechanism of injury, and location, this finding remained significant (OR 0.27, 0.21- 0.34, p<0.001). Massive transfusion was more common in hypothermia casualties n = 566 (19%) versus non-hypothermic recipients n = 1734 (6.9%), p <0.001.

Conclusions: Though the number of casualties that presented hypothermic was small, their injuries were more severe, and were more likely to receive massive blood transfusions. This cohort also had a higher mortality rate, a finding which held when adjusting for confounders. There appears to be an opportunity to improve hypothermia prevention for combat.

Blood Product Administration During the Role 1 Phase of Care: The Prehospital Trauma Registry Experience 

Andrew D Fisher, Matthew W Paulson, Jerome T McKay, James Bynum, Kathleen M Flarity, Michelle Howell, Vikhyat S Bebarta, Steven G Schauer 

Mil Med. 2020 Dec 24;usaa563. doi: 10.1093/milmed/usaa563 

Background: The majority of combat deaths occur in the prehospital setting. Efforts to increase survival including blood transfusions are made in the prehospital setting. The blood products available in the Role 1 setting include whole blood (WB), red blood cells (RBCs), fresh frozen plasma (FFP), and lyophilized (freeze-dried) plasma (FDP). 

Methods: This is a secondary analysis of a previously published dataset within the Prehospital Trauma Registry (PHTR) from 2003 through May 2019. Deterministic linking was used when possible with the DoD Trauma Registry for outcome data. Descriptive statistics were used to analyze the data. 

Results: We identified 1,357 patient encounters in the PHTR. Within that group, 28 patients received a prehospital blood product, with 41 total administrations: WB (18), RBCs (12), FFP (6), FDP (3), and blood not otherwise specified (2). Outcome data were available for 17 of the 28 patients. The median injury severity score was 20, with the thorax being the most frequent seriously injured body region. Most (94%) patients survived to discharge. The median ICU days was 11 (Interquartile Range [IQR] 3-19), and the median hospital days was 19 (IQR 8-29). The average volume (units) of RBCs was 6.0 (95% CI 1.9-10.1), WB 2.8 (95% CI 0.0-5.6), platelets 0.7 (95% CI 0.0-1.4), and FFP 5.0 (95% CI 1.2-8.8). 

Conclusions: The use of prehospital blood products is uncommon in U.S. combat settings. Patients who received blood products sustained severe injuries but had a high survival rate. Given the infrequent but critical use and potentially increased need for adequate prolonged casualty care in future near-peer conflicts, optimizing logistical chain circulation is required.

Ketamine Administration by Special Operations Medical Personnel During Training Mishaps 

Andrew D Fisher, Darin S Schwartz, Christopher D Petersen, Stephen E Meyer, Joseph N Thielemann, Theodore T Redman, Stephen C Rush 

J Spec Oper Med. Fall 2020;20(3):81-86 

Background: Opioids can have adverse effects on casualties in hemorrhagic shock. In 2014, the Committee on Tactical Combat Casualty Care (CoTCCC) recommended the use of ketamine at the point of injury (POI). Despite these recommendations the adherence is moderate at best. Poor use may stem from a lack of access to use ketamine during training. The United States Special Operations Command (USSOCOM) is often in a unique position, they maintain narcotics for use during all training events and operations. The goal of this work is to demonstrate that ketamine is safe and effective in both training and operational environments. 

Methods: This was a retrospective, observational performance improvement project within United States Special Operations Command and Air Combat Command that included the US Army's 75th Ranger Regiment, 160th Special Operations Aviation Regiment, and US Air Force Pararescue. Descriptive statistics were used to calculate the doses per administration to include the interquartile range (IQR), standard deviation (SD) and the range of likely doses using a 95% confidence interval (CI). A Wilcoxon signed-rank test was used to compare the mean pre-ketamine pain scores to the mean post-ketamine on a 0-to-10 pain scale. 

Results: From July 2010 to October 2017, there was a total of 34 patients; all were male. A total of 22 (64.7%) received intravenous ketamine and 12 (35.3%) received intramuscular ketamine and 8 (23.5%) received intranasal ketamine. The mean number of ketamine doses via all routes administered to patients was 1.88 (SD 1.094) and the mean total dose of all ketamine administration was 90.29mg (95% CI, 70.09-110.49). The mean initial dose of all ketamine administration was 47.35mg (95% CI, 38.52-56.18). The median preketamine pain scale for casualties was noted to be 8.0 (IQR 3) and the median post-ketamine pain scale was 0.0 (IQR 3). 

Conclusion: Ketamine appears to be safe and effective for use during military training accidents. Military units should consider allowing their medics to carry and use as needed.

The Relationship Between Severe Visual Acuity Loss, Traumatic Brain Injuries, and Ocular Injuries in American Service Members From 2001 to 2015 

Gerald Flanagan, Tom Velez, Weidong Gu, Eric Singman 

Mil Med. 2020 Sep 18;185(9-10):e1576-e1583 

Introduction: Although traumatic brain injury (TBI) is known to cause many visual problems, the correlation between the extent of severe visual acuity loss (SVAL) and severity of TBI has not been widely explored. In this retrospective analysis, combined information from Department of Defense (DoD)/Veterans Affairs ocular injury and TBI repositories were used to evaluate the relationship between chronic SVAL, TBI, ocular injuries, and associated ocular sequelae for U.S. service members serving between 2001 and 2015. 

Materials and methods: The Defense and Veterans Eye Injury and Vision Registry (DVEIVR) is an initiative led by the DoD and Veterans Affairs that consists of clinical and related data for service members serving in theater since 2001. The Defense and Veterans Brain Injury Center (DVBIC) is the DoD's office for tracking TBI data in the military and maintains data on active-duty service members with a TBI diagnosis since 2000. Longitudinal data from these 2 resources for encounters between February 2001 and October 2015 were analyzed to understand the relation between SVAL, and TBI while adjusting for ocular covariates such as open globe injury (OGI), disorders of the anterior segment and disorders of the posterior segment in a logistic regression model. TBI cases in DVEIVR were identified using DVBIC data and classified according to International Statistical Classification of Diseases criteria established by DVBIC. Head trauma and other open head wounds (OOHW) were also included. SVAL cases in DVEIVR were identified using both International Statistical Classification of Diseases criteria for blindness and low vision as well as visual acuity test data recorded in DVEIVR. 

Results: Data for a total of 25,193 unique patients with 88,996 encounters were recorded in DVEIVR from February, 2001 to November, 2015. Of these, 7,217 TBI and 1,367 low vision cases were identified, with 638 patients experiencing both. In a full logistic model, neither UTBI nor differentiated TBI (DTBI, ie, mild, moderate, severe, penetrating, or unclassified) were significant risk factors for SVAL although ocular injuries (disorders of the anterior segment, disorders of the posterior segment, and OGI) and OOHW were significant. 

Conclusion: Any direct injury to the eye or head risks SVAL but the location and severity will modify that risk. After adjusting for OGIs, OOHW and their sequelae, TBI was found to not be a significant risk factor for SVAL in patients recorded in DVEIVR. Further research is needed to explore whether TBI is associated with more moderate levels of vision acuity loss.

 

Management of hypoxaemia in the critically ill patient

Luke Flower, Daniel Martin

Br J Hosp Med (Lond) 2020 Jan 2;81(1):1-10 

Abstract

Hypoxaemia is a common presentation in critically ill patients, with the potential for severe harm if not addressed appropriately. This review provides a framework to guide the management of any hypoxaemic patient, regardless of the clinical setting. Key steps in managing such patients include ascertaining the severity of hypoxaemia, the underlying diagnosis and implementing the most appropriate treatment. Oxygen therapy can be delivered by variable or fixed rate devices, and non-invasive ventilation; if patients deteriorate they may require tracheal intubation and mechanical ventilation. Early critical care team involvement is a key part of this pathway.

Specialist treatments for severe hypoxaemia can only be undertaken on an intensive care unit and this field is developing rapidly as trial results become available. It is important that each new scenario is approached in a structured manner with an open diagnostic mind and a clear escalation plan.

VALIDATION OF A NOVEL PARTIAL REBOA DEVICE IN A SWINE HEMORRHAGIC SHOCK MODEL: FINE TUNING FLOW TO OPTIMIZE BLEEDING CONTROL AND REPERFUSION INJURY

Dominic Forte, Woo S Do, Jessica B Weiss, Rowan R Sheldon, John P Kuckelman, Benjamin A Cook, Tiffany C Levine, Matthew J Eckert, Matthew J Martin

J Trauma Acute Care Surg 2020 Apr 8; Online ahead of print 

Objectives: Partial restoration of aortic flow during REBOA is advocated by some to mitigate distal ischemia. Our lab has validated the mechanics and optimal partial REBOA flow rates using a prototype device (pREBOA). We hypothesize that pREBOA will increase survival when compared to full REBOA (fREBOA) in prolonged non-operative management of hemorrhagic shock.

Methods: 20 swine underwent placement of aortic flow probes, zone 1 REBOA placement, and 20% blood volume hemorrhage. They were randomized to either solid organ (SOI) or abdominal vascular (AVI) injury. The pREBOA arm (10 swine) underwent full inflation for 10min, then deflation to a flow rate of 0.5L/min for 2hr. The fREBOA arm (10 swine) underwent full inflation for 60min, followed by deflation/resuscitation. The primary outcome is survival, secondary outcomes are serologic/pathologic signs of ischemia-reperfusion injury and quantity of hemorrhage.

Results: 2/10 swine survived in the fREBOA group (2/5 SOI, 0/5 AVI) v. 7/10 surviving in the pREBOA group (3/5 SOI, 4/5 AVI). Survival was increased (p=.03) and hemorrhage was higher in the pREBOA group (SOI 1.36±.25kg v. 0.70±.33kg, p = 0.007; 0.86±.22kg v. 0.71±.28kg, not significant). Serum evidence of ischemia was greater with fREBOA, but this was not significant (e.g. Lactate 16.91±3.87 mg/dL v. 12.96±2.48 mg/dL at 120min, not significant). Swine treated with pREBOA that survived demonstrated trends towards lower ALT, lower potassium, and higher calcium. The potassium was significantly lower in survivors at 60min and 90min time points (5.97±0.60 v. 7.53±0.90, p=.011; 6.67±0.66 v. 8.15±0.78, p=.029). Calcium was significantly higher at 30min, 60min, 90min (8.56±0.66 v. 7.50±0.40, p=.034; 8.63±0.62 v. 7.15±0.49, p=.019; 8.96±0.64 v. 7.00, p=.028).

Conclusion: Prolonged pREBOA at a moderate distal flow rate provided adequate hemorrhage control, improved survival, and had evidence of decreased ischemic injury versus fREBOA. Prophylactic aggressive calcium supplementation may have utility prior to and during the reperfusion phase.

Study type: Basic Science (Original Article) LEVEL OF EVIDENCE: III.

The utility of the brain trauma evidence to inform paramedic rapid sequence intubation in out-of-hospital stroke

Pieter Francsois Fouche, Paul Andrew Jennings, Malcolm Boyle, Stephen Bernard, Karen Smith

BMC Emerg Med 2020 Jan 28;20(1):5 

Abstract

Background: Rapid sequence intubation (RSI) is used to secure the airway of stroke patients. Randomized controlled trial evidence exists to support the use of paramedic RSI for traumatic brain injury (TBI), but cannot necessarily be applied to stroke RSI because of differences between the stroke and TBI patient. To understand if the TBI evidence can be used for stroke RSI, we analysed a retrospective cohort of TBI and strokes to compare how survival is impacted differently by RSI when comparing strokes and TBI.

Methods: This study was a retrospective analysis of 10 years of in-hospital and out-of-hospital data for all stroke and TBI patients attended by Ambulance Victoria, Australia. Logistic regression predicted the survival for ischemic and haemorrhagic strokes as well as TBI. The constituents of RSI, such a medications, intubation success and time intervals were analysed against survival using interactions to asses if RSI impacts survival differently for strokes compared to TBI.

Results: This analysis found significant interactions in the RSI-only group for age, number of intubation attempts, atropine, fentanyl, pulse rate and perhaps scene time and time- to-RSI. Such interactions imply that RSI impact survival differently for TBI versus strokes. Additionally, no significant difference in survival for TBI was found, with a - 0.7% lesser survival for RSI compared to no-RSI; OR 0.86 (95% CI 0.67 to 1.11; p = 0.25). Survival for haemorrhagic stroke was - 14.1% less for RSI versus no-RSI; OR 0.44 (95% CI 0.33 to 0.58; p = 0.01) and was - 4.3%; OR 0.67 (95% CI 0.49 to 0.91; p = 0.01) lesser for ischemic strokes.

Conclusions: Rapid sequence intubation and related factors interact with stroke and TBI, which suggests that RSI effects stroke survival in a different way from TBI. If RSI impact survival differently for strokes compared to TBI, then perhaps the TBI evidence cannot be used for stroke RSI.

Evaluation of helmet and goggle designs by modeling non-penetrating projectile impacts

Rinat Friedman, Ayelet Haimy, Yoram Epstein, Amit Gefen

Comput Methods Biomech Biomed Engin 2019 Feb;22(3):229-242

Abstract

Despite the progress in developing personal combat-protective gear, eye and brain injuries are still widely common and carry fatal or long-term repercussions. The complex nature of the cranial tissues suggests that simple methods (e.g. crash-dummies) for testing the effectiveness of personal protective gear against non-penetrating impacts are both expensive and ineffective, and there are ethical issues in using animal or cadavers. The present work presents a versatile testing framework for quantitatively evaluating protective performances of head and eye combat-protective gear, against non-penetrating impacts. The biomimetic finite element (FE) head model that was developed provides realistic representation of cranial structure and tissue properties. Simulated crash impact results were validated against a former cadaveric study and by using a crash-phantom developed in our lab. The model was then fitted with various helmet and goggle designs onto which a non-penetrating ballistic impact was applied. Example data show that reduction of the elastic and shear moduli by 30% and 80% respectively of the helmet outer Kevlar-29 layer, lowered intracranial pressures by 20%. Our modeling suggests that the level of stresses that develop in brain tissues, which ultimately cause the brain damage, cannot be predicted solely by the properties of the helmet/goggle materials. We further found that a reduced contact area between goggles and face is a key factor in reducing the mechanical loads transmitted to the optic nerve and eye balls following an impact. Overall, this work

demonstrates the simplicity, flexibility and usefulness for development, evaluation, and testing of combat-protective equipment using computational modeling. Highlights A finite element head model was developed for testing head gear. Reduced helmet's outer layer elastic and shear moduli lowered intracranial stresses. Gear material properties could not fully predict impact- related stress in the brain. Reduced goggles-face contact lowered transmitted loads to the optic nerve and eyes.

Cerebrovascular Response to Propofol, Fentanyl, and Midazolam in Moderate/Severe Traumatic Brain Injury: A Scoping Systematic Review of the Human and Animal Literature

 Logan Froese, Joshua Dian, Carleen Batson, Alwyn Gomez, Bertram Unger, Frederick A Zeiler

 Neurotrauma Rep. 2020 Oct 13;1(1):100-112

 Abstract

 Intravenous propofol, fentanyl, and midazolam are utilized commonly in critical care for metabolic suppression and anesthesia. The impact of propofol, fentanyl, and midazolam on cerebrovasculature and cerebral blood flow (CBF) is unclear in traumatic brain injury (TBI) and may carry important implications, as care is shifting to focus on cerebrovascular reactivity monitoring/directed therapies. The aim of this study was to perform a scoping review of the literature on the cerebrovascular/CBF effects of propofol, fentanyl, and midazolam in human patients with moderate/severe TBI and animal models with TBI. A search of MEDLINE, BIOSIS, EMBASE, Global Health, SCOPUS, and the Cochrane Library from inception to May 2020 was performed. All articles were included pertaining to the administration of propofol, fentanyl, and midazolam, in which the impact on CBF/cerebral vasculature was recorded. We identified 14 studies: 8 that evaluated propofol, 5 that evaluated fentanyl, and 2 that evaluated midazolam. All studies suffered from significant limitations, including: small sample size, and heterogeneous design and measurement techniques. In general, there was no significant change seen in CBF/cerebrovascular response to administration of propofol, fentanyl, or midazolam during experiments where PCO2 and mean arterial pressure (MAP) were controlled. This review highlights the current knowledge gap surrounding the impact of commonly utilized sedative drugs in TBI care. This work supports the need for dedicated studies, both experimental and human-based, evaluating the impact of these drugs on CBF and cerebrovascular reactivity/response in TBI.

Prehospital Point of Care Testing for the Early Detection of Shock and Prediction of Lifesaving Interventions

Samuel M Galvagno Jr, Robert A Sikorski, Douglas J Floccare, Peter Rock, Michael A Mazzeffi, Joseph J DuBose, Thomas M Scalea, Catriona Miller, Justin E Richards, James V O'Connor, Colin F Mackenzie, Peter Hu

Shock 2020 May 21; Online ahead of print 

Introduction: Early diagnosis and treatment are essential for enhancing outcomes for the traumatically injured. In this prospective prehospital observational study, we hypothesized that a variety of laboratory results measured in the prehospital environment would predict both the presence of early shock and the need for LSIs for adult patients with traumatic injuries.

Methods: Adult trauma patients flown by a helicopter emergency medical service were prospectively enrolled. Using an i-STAT® portable analyzer, data from sixteen laboratory tests were collected. Vital signs data were also collected. Outcomes of interest included detection of shock, mortality, and requirement for lifesaving interventions (LSIs). Logistic regression, including a Bayesian analysis, was performed.

Results: Among 300 patients screened for enrollment, 261 had complete laboratory data for analysis. The majority of patients were male (75%) with blunt trauma (91.2%). The median injury severity score was 29 (IQR, 25-75) and overall mortality was 4.6%. A total of 170 LSIs were performed. The median lactate for patients who required a LSI was 4.1 (IQR, 3-5.4). The odds of requiring a LSI within the first hour of admission to the trauma center was highly associated with increases in lactate and glucose. A lactate level > 4 mmol/L was statistically associated with greater sensitivity and specificity for predicting the need for a LSI compared to shock index.

Conclusions: In this prospective observational trial, lactate outperformed static vital signs, including shock index, for detecting shock and predicting the need for LSIs. A lactate level > 4 mmol/L was found to be highly associated with the need for LSIs.

Applying trauma systems concepts to humanitarian battlefield care: a qualitative analysis of the Mosul trauma pathway

Kent Garber, Adam L Kushner, Sherry M Wren, Paul H Wise, Paul B Spiegel Confl Health 2020 Feb 4;14:5 

Abstract

Background: Trauma systems have been shown to save lives in military and civilian settings, but their use by humanitarians in conflict settings has been more limited. During the Battle of Mosul (October 2016-July 2017), trauma care for injured civilians was provided through a novel approach in which humanitarian actors were organized into a trauma pathway involving echelons of care, a key component of military trauma systems. A better understanding of this approach may help inform trauma care delivery in future humanitarian responses in conflicts.

Methodology: A qualitative study design was used to examine the Mosul civilian trauma response. From August-December 2017, in-depth semi-structured interviews were conducted with stakeholders (n = 54) representing nearly two dozen organizations that directly participated in or had first-hand knowledge of the response. Source document reviews were also conducted. Responses were analyzed in accordance with a published framework on civilian battlefield trauma systems, focusing on whether the response functioned as an integrated trauma system. Opportunities for improvement were identified.

Results: The Mosul civilian trauma pathway was implemented as a chain of care for civilian casualties with three successive echelons (trauma stabilization points, field hospitals, and referral hospitals). Coordinated by the World Health Organization, it comprised a variety of actors, including non-governmental organizations, civilian institutions, and at least one private medical company. Stakeholders generally felt that this approach improved access to trauma care for civilians injured near the frontlines compared to what would have been available.

Several trauma systems elements such as transportation, data collection, field coordination, and post-operative rehabilitative care might have been further developed to support a more integrated system.

Conclusions: The Mosul trauma pathway evolved to address critical gaps in trauma care during the Battle of Mosul. It adapted the concept of echelons of care from western military practice to push humanitarian actors closer to the frontlines and improve access to care for injured civilians. Although efforts were made to incorporate some of the integrative components (e.g. evidence-based pre-hospital care, transportation, and data collection) that have enabled recent achievements by military trauma systems, many of these proved difficult to implement in the Mosul context. Further discussion and research are needed to determine how trauma systems insights can be adapted in future humanitarian responses given resource, logistical, and security constraints, as well as to clarify the responsibilities of various actors.

Association of resuscitative endovascular balloon occlusion of the aorta (REBOA) and mortality in penetrating trauma patients 

Alberto F García, Ramiro Manzano-Nunez, Claudia P Orlas, Juan Ruiz-Yucuma, Alejandra Londoño, Camilo Salazar, Juan Melendez, Álvaro I Sánchez, Juan Carlos Puyana, Carlos A Ordoñez

Eur J Trauma Emerg Surg 2020 Apr 16. doi: 10.1007/s00068-020-01370-9 

Purpose: The purpose of this study was to examine the association of REBOA and mortality in a group of patients with penetrating trauma to the torso, treated in a level-I trauma center from Colombia.

Methods: In a retrospective cohort study, patients with penetrating trauma, requiring emergency surgery, and treated between 2014 and 2018, were included. The decision to use or not use REBOA during emergent surgery was based on individual surgeon's opinion. A propensity score (PS) was calculated after adjusting for age, clinical signs on admission (systolic blood pressure, cardiac rate, Glasgow coma scale), severe trauma in thorax and abdomen, and the presence of non-compressive torso hemorrhage. Subsequently, logistic regression for mortality was adjusted for the number of red blood cells (RBC) transfused within the first six hours after admission, injury severity score (ISS), and quintiles of PS.

Results: We included 345 patients; 28 of them (8.1%) were treated with REBOA. Crude mortality rates were 17.9% (5 patients) in REBOA group and 15.3% (48 patients) in control group (p = 0.7). After controlling for RBC transfused, ISS, and the PS, the odds of death in REBOA group was 78% lower than that in the control group (odds ratio [OR] 0.20, 95% confidence interval [95%CI] 0.05-0.77, p = 0.01).

Conclusion: We found that, when compared to no REBOA use, patients treated with REBOA had lower risk-adjusted odds of mortality. These findings should be interpreted with caution and confirmed in future comparative studies, if possible.

Military Teleophthalmology in Afghanistan Using Mobile Phone Application

William G Gensheimer, Kyle E Miller, Jennifer Stowe, Jeanette Little, Gary L Legault

JAMA Ophthalmol. 2020 Oct 1;138(10):1053-1060 

Importance: The coronavirus disease 2019 pandemic has highlighted the need to expand telemedicine solutions.

Objective: To beta test a secure teleophthalmology mobile app at military treatment facilities in Afghanistan.

Design, setting, and participants: This prospective case series included 16 military treatment facilities at diverse roles of care including forward operating bases in Afghanistan and 1 location outside of Afghanistan. Thirty point-of-care medics and medical professionals were included from September to November 2019.

Interventions: Users placed teleophthalmology consults on their mobile phone using the mobile eye care app, and an expeditionary ophthalmologist stationed at a military hospital in Afghanistan responded. Users graded the mobile app using a rating scale from 1 to 5, with 1 being very dissatisfied and 5 being very satisfied.

Main outcomes and measures: Mean initial response time, agreement between the teleophthalmology diagnosis and final diagnosis, treatment and management following recommendations outlined in the Joint Trauma System clinical practice guidelines, prevention of the need for aeromedical evacuation, user satisfaction, and security and the Health Insurance Portability and Accountability Act compliance of consult.

Results: There were 28 consults placed over 6 weeks by 18 different users that were received by the expeditionary ophthalmologist. The mean (SD) patient age was 30.3 (9.8) years. Most patients were male (26 [93%]) and active duty US military (22 [78%]). The mean initial response time was 3 minutes 58 seconds (95% CI, 2 minutes 30 seconds to 5 minutes 26 seconds). There was agreement between the teleophthalmology diagnosis and final diagnosis in 24 consults (86%; 95% CI, 72%-100%). The treatment and management followed recommendations outlined in the Joint Trauma System Clinical Practice Guidelines for Eye Trauma: Initial Care in 28 consults (100%). Teleophthalmology consultation prevented the need for aeromedical evacuation in 4 consults (14%; 95% CI, 0.7%-28%). The patient returned to duty in 15 consults (54%; 95% CI, 34%-73%). Median overall satisfaction was 5 (minimum, 3; maximum, 5). All 28 consults (100%) were secure and compliant with the Health Insurance Portability and Accountability Act.

Conclusions and relevance: While only a limited number of consults were evaluated, this study suggests that teleophthalmology mobile phone apps may improve and extend ophthalmic care in combat zones.

Tranexamic Acid; A Glittering Player in the Field of Trauma

 Fariborz Ghaffarpasand, Hamid Reza Abbasi, Shahram Bolandparvaz, Shahram Paydar, Maryam Dehghankhalili

Bull Emerg Trauma 2020 Apr;8(2):53-55 

No abstract available

Dissociative and Analgesic Properties of Ketamine Are Independent

Jacob Gitlin, Shubham Chamadia, Joseph J Locascio, Breanna R Ethridge, Juan C Pedemonte, Eunice Y Hahm, Reine Ibala, Jennifer Mekonnen, Katia M Colon, Jason Qu, Oluwaseun Akeju

 Anesthesiology. 2020 Nov 1;133(5):1021-1028 

Background: Ketamine is a dissociative anesthetic with analgesic properties. Ketamine's analgesic properties have been suggested to result from its dissociative properties. To the authors' knowledge, this postulate is unsubstantiated. The authors hypothesize that the dissociative and analgesic properties of ketamine are independent.

 Methods: The authors conducted a single-site, open-label study of ketamine anesthesia (2 mg/kg) in 15 healthy subjects. Midazolam was administered at a prespecified time point to attenuate dissociation. The authors longitudinally assessed precalibrated cuff pain intensity and quality using Patient-Reported Outcomes Measurement Information System questionnaires, and dissociation, using the Clinician Administered Dissociative States Scale. Mixed effects models were used to assess whether dissociation accounted for the effect of ketamine on pain intensity and quality. 

Results: The dissociation model demonstrated an inverted U-shaped quadratic relationship between time and dissociation scores. Additive to this effect, midazolam reduced the dissociation adjusted means by 10.3 points (95% CI, 3.4 to 17.1; P = 0.005). The pain intensity model also demonstrated a U-shaped quadratic relationship between time and pain intensity. When the pain intensity model was reanalyzed with dissociation scores as an additional covariate, the dissociation term was not retained in the model, and the other effects were preserved in direction and strength. This result was conserved for nociceptive and neuropathic pain quality. 

Conclusions: Ketamine's analgesic properties are not exclusively caused by dissociation. Thus, ketamine may be used as a probe to advance our knowledge of dissociation independent neural circuits that encode pain.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) for Thoracic Trauma: A Translational Swine Study

Jacob J Glaser, Leslie E Neidert, Clifford G Morgan, Megan Brenner, Kyle S Stigall, Sylvain Cardin

J Trauma Acute Care Surg 2020 Apr 16; Online ahead of print. 

Non-compressible torso hemorrhage in trauma is particularly lethal. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) has the potential to stabilize these patients, but currently is contraindicated for major thoracic bleeding. The goal of this study was to evaluate the effect of REBOA on the hemodynamic and metabolic profile as well as its effect on early survival in a porcine model of thoracic hemorrhage and shock.

Methods: Forty-eight (48) male Yorkshire swine (60-80kg) underwent 30% hemorrhage and were randomized to three thoracic injuries, with and without Zone 1 REBOA occlusion: pulmonary parenchymal injury (PI), thoracic venous injury (VI), or subclavian artery injury (AI). Following hemorrhage, thoracic injuries were induced (T0) and allowed to bleed freely. REBOA groups had Zone 1 occlusion after the thoracic injury, with deflation at T30. All groups had whole blood resuscitation at T30 and were euthanized at T90. Survival, total blood loss, mean arterial pressure (MAP), end tidal CO2 (EtCO2), and arterial blood gas parameters were analyzed. Statistical significance was determined by t-tests and two-way repeated measures ANOVA.

Results: The use of REBOA improved the hemodynamics in all three injury patterns, with no differences observed in the outcomes of short-term survival and thoracic blood loss between the REBOA and non-REBOA groups. All groups showed equivalent changes in markers of shock (pH, HCO3, and Base Excess) prior to resuscitation.

Conclusion: In this animal study of hemorrhage and major thoracic bleeding, the addition of Zone 1 REBOA did not significantly affect short-term survival or blood loss, while providing hemodynamic stabilization. Therefore in non-compressible thoracic bleeding, without immediate surgical capability, long-term outcomes may be improved with REBOA, and thoracic hemorrhage should not be considered contraindications to REBOA use.

Level of evidence: Level I Therapeutic/Care Management Study.

Successful endotracheal intubation following a failed first attempt during aeromedical retrieval

John Glasheen, Jeff Hooper, Andrew Donohue, Emmeline Finn, Bronwyn Murray-Smith, Renée Bolot, Mark Edwards

Emerg Med J 2020 May;37(5):314-318 

Abstract

Introduction: First attempt intubation success is used by many prehospital services as a marker of quality and safety. An increasing complication rate is associated with repeated intubation attempts. The aim of this study was to identify changes to intubation technique following a failed intubation attempt.

Methods: LifeFlight Retrieval Medicine provides aeromedical retrieval services in Queensland, Australia. This retrospective study identified cases of failed intubation attempts from an electronic database registry over a 41-month period from March 2015 to July 2018. These data were analysed using descriptive statistics.

Results: Of the 762 patients who required intubation 758 (99.5%) were successfully intubated, with 684 intubated at the first attempt (89.8%; 95% CI: 0.87 to 0.92). There was no difference in first attempt success between direct and video laryngoscopy (511/563 (90.8%) vs 172/194 (88.6%) p=0.38), trauma or medical (374/419 (89.3%) vs 310/343 (90.4%), p=0.61), primary or interhospital missions (329/370 (88.7%) vs 355/392 (90.8%), p=0.33). 78 cases of failed first attempt intubations were identified. In 65 of these cases, intubation was successful at the second attempt. A single change was made to the intubation procedure prior to a second successful attempt in 28/78 cases (35.9%), and more than one change was made in 41/78 (52.6%). The changes included the operator, intubation device, patient position, intubating aid and external laryngeal manipulation. No change between attempts was recorded in 9/78 (11.5%). 9 cases were successfully intubated at the third attempt, and changes prior to the third attempt included operator, device and intubating aid.

Conclusion: Although a high overall intubation success was found, one in ten patients who were intubated had a failed first attempt. The majority of successful subsequent attempts were preceded by at least one change to intubating technique. Intubating clinicians need the ability to identify and correct issues leading to a failed first attempt.

A comparison of the breathing apparatus deadspace associated with a supraglottic airway and endotracheal tube using volumetric capnography in young children

 Eduardo J Goenaga-Díaz, L Daniela Smith, Shelly H Pecorella, Timothy E Smith, Gregory B Russell, Kathleen N Johnson, Martina G Downard, Douglas G Ririe, Dudley E Hammon, Ashley S Hodges, T Wesley Templeton 

Korean J Anesthesiol. 2020 Nov 17. doi: 10.4097/kja.20518 

Background: Supraglottic airway devices including the air-Q® are being used with increasing frequency for elective anesthetics in infants and younger pediatric patients. To date, there is minimal research documenting the potentially significant airway dead space these devices may contribute to the ventilation circuit when compared to an endotracheal tube (ETT). 

Methods: In a prospective cohort study, 59 pediatric patients between the ages of 3 months and 6 years, weighing between 5 and 20 kg, and scheduled for outpatient urologic or general surgery procedures were recruited. An air-Q® or ETT was inserted at the discretion of the attending anesthesiologist, and tidal volume, respiratory rate, and end-tidal CO2 were controlled according to protocol. Ventilatory parameters including airway dead space were recorded or calculated using volumetric capnography every two minutes for 10 minutes. 

Results: Groups were similar in demographics. There was a significant difference in weight-adjusted dead space volume between the air-Q® and ETT groups, 4.1 ± 0.8 mL/kg versus 3.0 ± 0.7 mL/kg, respectively (p<0.0001). Weight-adjusted dead space volume (in mL/kg) increased significantly with decreasing weight for both the air-Q® and ETT groups. 

Conclusion: In healthy children undergoing positive pressure ventilation for elective surgery, the air-Q® supraglottic airway introduces significantly greater airway dead space than an endotracheal tube. Additionally, airway dead space, and minute ventilation required to maintain normocarbia, appear to increase with decreasing patient weight irrespective of whether a supraglottic airway or endotracheal tube is used.

Lyophilized platelets versus cryopreserved platelets for management of bleeding in thrombocytopenic dogs: A multicenter randomized clinical trial

 Robert Goggs, Benjamin M Brainard, Dana N LeVine, Janine Calabro, Karyn Harrell, Tracy Mills, Richard Stone, Benjamin Davidson, Christine Iacovetta, Lauren Harris 10, John Gicking, Mary Aslanian, Ashley Ziegler, Brenda Fulcher, Teresa Lightfoot, Meredith Miller, John Loftus, Rebecca Walton, April Blong, Jennifer Kishbaugh Anne S Hale

J Vet Intern Med. 2020 Nov;34(6):2384-2397 

Background: Thrombocytopenia in dogs is common in critical care medicine, but availability of fresh platelet concentrates in veterinary medicine can be limiting. Lyophilized platelets have long shelf-lives and can be easily transported, stored, and administered in various settings. 

Objective: To evaluate the efficacy and safety of a novel trehalose-stabilized canine lyophilized platelet product in thrombocytopenic dogs with clinically-evident bleeding. 

Animals: Eighty-eight dogs with platelet counts <50 × 103 /μL and a standardized bleeding assessment tool (DOGiBAT) score ≥2. 

Methods: Multicenter, randomized, non-blinded, non-inferiority clinical trial comparing dimethyl sulfoxide (DMSO)-stabilized cryopreserved platelet concentrates (CPP) with trehalose-stabilized lyophilized platelets (LP) for control of bleeding in thrombocytopenic dogs. Dogs were randomized to receive 3 × 109 platelets/kg of LP or CPP. Primary outcome measures were change in DOGiBAT score, platelet count, need for additional red cell transfusion and all-cause mortality. 

Results: Fifty dogs received LP and 38 received CPP. Baseline demographics and clinical characteristics of both groups were comparable. At 1-hour post-transfusion, LP were superior for change in DOGiBAT score, and non-inferior at 24-hours post-transfusion. The LP were non-inferior to CPP for change in platelet count, need for additional red blood cell units, and survival to discharge. The LP were superior for change in hematocrit at 1-hour post-transfusion, and non-inferior at 24-hours. No adverse effects were noted in either group. 

Conclusions and clinical importance: A novel trehalose-stabilized canine LP product appears to be logistically superior and is clinically non-inferior to DMSO-stabilized canine CPP for management of bleeding in thrombocytopenic dogs.

Rapid Ultrasound for Shock and Hypotension: A Clinical Update for the Advanced Practice Provider: Part 2

 Juan M Gonzalez, Johis Ortega, Nichole Crenshaw, Lila de Tantillo

Adv Emerg Nurs J. Oct/Dec 2020;42(4):284-292 

Abstract 

The Rapid Ultrasound for Shock and Hypotension (RUSH) examination is used for patients with hypotension without clear cause or undifferentiated hypotension. In the emergency department setting, clinicians may perform the RUSH examination to supplement the physical assessment and differentiate the diagnosis of hypovolemic, obstructive, cardiogenic, and distributive forms of shock. The key elements of the RUSH examination are the pump, tank, and pipes, meaning potentially causes of the hypotension are examined within the heart, vascular volume and integrity, and the vessels themselves. Clinicians follow a systemic protocol to seeking evidence of specific conditions including heart failure exacerbation, cardiac tamponade, pleural effusion, pneumothorax, abdominal aortic aneurysm, and deep vein thrombosis. Because ultrasonography is a user-dependent skill, the advanced practice nurse in the emergency department should be educated regarding the RUSH protocol and prepared to implement the examination.

Evaluation of Three Methods for CPR Training to Lifeguards: A Randomised Trial Using Traditional Procedures and New Technologies

 Daniel González-Santano, Daniel Fernández-García, Elena Silvestre-Medina, Beatriz Remuiñán-Rodríguez, Fernando Rosell-Ortiz, Juan Gómez-Salgado, María Sobrido-Prieto, Beatriz Ordás-Campos, Santiago Martínez-Isasi

 Medicina (Kaunas). 2020 Oct 30;56(11):577 

Background and objectives: When the drowning timeline evolves and drowning occurs, the lifeguard tries to mitigate the event by applying the last link of the drowning survival chain with the aim of treating hypoxia. Quality CPR (Cardiopulmonary Resuscitation) and the training of lifeguards are the fundamental axes of drowning survival. Mobile applications and other feedback methods have emerged as strong methods for the learning and training of basic CPR in the last years so, in this study, a randomised clinical trial has been carried out to compare the traditional method as the use of apps or manikins with a feedback system as a method of training to improve the quality of resuscitation. Materials and Methods: The traditional training (TT), mobile phone applications (AP) and feedback manikins (FT) are compared. The three cohorts were subsequently evaluated through a manikin providing feedback, and a data report on the quality of the manoeuvres was obtained. Results: Significant differences were found between the traditional manikin and the manikin with real-time feedback regarding the percentage of compressions with correct depth (30.8% (30.4) vs. 68.2% (32.6); p = 0.042). Hand positioning, percentage correct chest recoil and quality of compressions exceeded 70% of correct performance in all groups with better percentages in the FT (TT vs. FT; p < 0.05). Conclusions: As a conclusion, feedback manikins are better learning tools than traditional models and apps as regards training chest compression. Ventilation values are low in all groups, but improve with the feedback manikin.

Ertapenem and Faropenem against Mycobacterium tuberculosis: in vitro testing and comparison by macro and microdilution

 Ximena Gonzalo, Giovanni Satta, Julio Ortiz Canseco, Timothy D McHugh, Francis Drobniewski 

BMC Microbiol. 2020 Aug 31;20(1):271 

Background: Interest in carbapenems has been rising in the last few years due to the emergence of drug resistant tuberculosis. Ertapenem (ETP), given once a day parenteral, and faropenem (FAR), oral, have a better administration profile than meropenem (MEM), imipenem (IPM) and doripenem (DOR). The addition of amoxicillin-clavulanate (AMC) inhibits the hydrolysis by the carbapenemase present in Mycobacterium tuberculosis (MTB). The aim of this study was to determine the in vitro activity of ETP and FAR against susceptible and resistant clinical MTB strains by two widely use methodologies, the BACTEC960 MGIT and microdilution. 

Results: 19 clinical isolates with different susceptibility profiles and H37Rv were included. Minimal inhibitory concentration (MIC) testing was performed using two methods of different concentrations of ETP and FAR with and without AMC. MIC50 was 2 and 8 for FAR with and without AMC by both methods. MIC90 was > 16 and > 8 by microdilution and MGIT respectively and did not change after AMC addition. 18/20 samples were resistant to the highest concentration of ETP, with and without AMC. Half of the samples had some susceptibility to FAR; addition of AMC further reduced the MIC level in seven isolates. 10/20 isolates showed susceptibility to FAR and the addition of AMC further reduced the MIC in 7 isolates. However, most of the MICs were near the limit of effectiveness (8 μg/mL). Resistance to FAR was associated with resistance to MEM (p = 0.04) but not to resistance profiles of other drugs, including M/XDR status. 

Conclusions: The lack of ETP activity may be associated with its degradation, independent of carbapenemase, during incubation. No susceptibility pattern to traditional drugs can predict susceptibility to FAR and susceptibility testing is not routinely available. PK/PD studies are needed as reaching the concentrations tested in these experiments may be challenging. This work highlighted some of the limitations of carbapenem use. More evidence is needed to clarify their true impact in TB treatment and outcome, considering the financial burden, complications and microbiota changes associated with their use.

Defining a Research Agenda for Layperson Prehospital Hemorrhage Control: A Consensus Statement

 Eric Goralnick, Chibuike Ezeibe, Muhammad Ali Chaudhary, Justin McCarty, Juan P Herrera-Escobar, Tomas Andriotti, Elzerie de Jager, Daniel Ospina-Delgado, Craig Goolsby, Richard Hunt, Joel S Weissman, Adil Haider, Lenworth Jacobs, Stop the Bleed National Research Agenda Consensus Conference Working Group; Erin Andrade, Jeremy Brown, Eileen M Bulger, Frank K Butler, David Callaway, Edward J Caterson, Niteesh K Choudhry, Michael R Davis, Alex Eastman, Brian J Eastridge, Jonathan L Epstein, Conor L Evans, Marianne Gausche-Hill, Mark L Gestring, Scott A Goldberg, Dan Hanfling, John Bradley Holcomb, Carl-Oscar Jonson, David R King, Sean Kivlehan, Russ S Kotwal, Jon R Krohmer, Nomi Levy-Carrick, Matthew Levy, Joan José Meléndez Lugo, David P Mooney, Matthew D Neal, Robert Niskanen, Patrick O'Neill, Habeeba Park, Peter T Pons, Erik Prytz, Todd E Rasmussen, Michael A Remley, Robert Riviello, Ali Salim, Stacy Shackelfold, E Reed Smith, Ronald M Stewart, Mamta Swaroop, Kevin Ward, Tarsicio Uribe-Leitz, Molly P Jarman, Gezzer Ortega

 JAMA Netw Open. 2020 Jul 1;3(7):e209393 

Importance: Trauma is the leading cause of death for US individuals younger than 45 years, and uncontrolled hemorrhage is a major cause of trauma mortality. The US military's medical advancements in the field of prehospital hemorrhage control have reduced battlefield mortality by 44%. However, despite support from many national health care organizations, no integrated approach to research has been made regarding implementation, epidemiology, education, and logistics of prehospital hemorrhage control by layperson immediate responders in the civilian sector. 

Objective: To create a national research agenda to help guide future work for prehospital hemorrhage control by laypersons. 

Evidence review: The 2-day, in-person, National Stop the Bleed (STB) Research Consensus Conference was conducted on February 27 to 28, 2019, to identify and achieve consensus on research gaps. Participants included (1) subject matter experts, (2) professional society-designated leaders, (3) representatives from the federal government, and (4) representatives from private foundations. Before the conference, participants were provided a scoping review on layperson prehospital hemorrhage control. A 3-round modified Delphi consensus process was conducted to determine high-priority research questions. The top items, with median rating of 8 or more on a Likert scale of 1 to 9 points, were identified and became part of the national STB research agenda. 

Findings: Forty-five participants attended the conference. In round 1, participants submitted 487 research questions. After deduplication and sorting, 162 questions remained across 5 a priori-defined themes. Two subsequent rounds of rating generated consensus on 113 high-priority, 27 uncertain-priority, and 22 low-priority questions. The final prioritized research agenda included the top 24 questions, including 8 for epidemiology and effectiveness, 4 for materials, 9 for education, 2 for global health, and 1 for health policy. 

Conclusions and relevance: The National STB Research Consensus Conference identified and prioritized a national research agenda to support laypersons in reducing preventable deaths due to life-threatening hemorrhage. Investigators and funding agencies can use this agenda to guide their future work and funding priorities.

Beyond validation: getting health apps into clinical practice

William J Gordon, Adam Landman, Haipeng Zhang, David W Bates

NPJ Digit Med 2020 Feb 3;3:14 

Abstract

Fueled by advances in technology, increased access to smartphones, and capital investment, the number of available health "apps" has exploded in recent years. Patients use their smartphones for many things, but not as much as they might for health, especially for managing their chronic conditions. Moreover, while significant work is ongoing to develop, validate, and evaluate these apps, it is less clear how to effectively disseminate apps into routine clinical practice. We propose a framework for prescribing apps and outline the key issues that need to be addressed to enable app dissemination in clinical care. This includes: education and awareness, creating digital formularies, workflow and EHR integration, payment models, and patient/provider support. As work in digital health continues to expand, integrating health apps into clinical care delivery will be critical if digital health is to achieve its potential.

Ultrasound for airway management: An evidence-based review for the emergency clinician

Michael Gottlieb, Dallas Holladay, Katharine M Burns, Damali Nakitende, John Bailitz Am J Emerg Med 2020 May;38(5):1007-1013 

Abstract

Background: Airway management is a common procedure performed in the Emergency Department with significant potential for complications. Many of the traditional physical examination maneuvers have limitations in the assessment and management of difficult airways. Point-of-care ultrasound (POCUS) has been increasingly studied for the evaluation and management of the airway in a variety of settings.

Objective: This article summarizes the current literature on POCUS for airway assessment, intubation confirmation, endotracheal tube (ETT) depth assessment, and performing cricothyroidotomy with an emphasis on those components most relevant for the Emergency Medicine clinician.

Discussion: POCUS can be a useful tool for identifying difficult airways by measuring the distance from the skin to the thyrohyoid membrane, hyoid bone, or epiglottis. It can also predict ETT size better than age-based formulae. POCUS is highly accurate for confirming ETT placement in adult and pediatric patients. The typical approach involves transtracheal visualization but can also include lung sliding and diaphragmatic elevation. ETT depth can be assessed by visualizing the ETT cuff in the trachea, as well as using lung sliding and the lung pulse sign. Finally, POCUS can identify the cricothyroid membrane more quickly and accurately than the landmark-based approach.

Conclusion: Airway management is a core skill in the Emergency Department. POCUS can be a valuable tool with applications ranging from airway assessment to dynamic cricothyroidotomy. This paper summarizes the key literature on POCUS for airway management.

Brief report on combat trauma surgical training using a perfused cadaver model

Daniel Grabo, Travis Polk, Michael Minneti, Kenji Inaba, Demetrios Demetriades J Trauma Acute Care Surg 2020 Aug;89(2S Suppl 2):S175-S179 

Background: Surgical combat casualty care presents difficult training challenges. Although several high-fidelity simulation (SIM) techniques have emerged, none are able to fully integrate the many intricacies involved in the care of a complex trauma patient. Herein, we report the use of perfused fresh human cadaver model for training and assessment of forward surgical teams (FSTs).

Methods: Forward surgical teams attend a 4-day combat trauma surgical skills course including focused on trauma exposures. A half-day SIM involves the entire surgical team in four sequential surgical scenarios that involve the neck, chest, abdomen, and extremities, as well as airway management and resuscitation. Teams undergo immediate debriefing and videotape review of team dynamics and technical skills, as well as times to completion of critical interventions.

Results: The data evaluated include five initial demonstration courses in which training metrics were available. Each team included both a junior and experienced surgeon, anesthesiologists, and surgical scrub technicians. As FSTs progressed through SIMs, they demonstrated improvements in team dynamics and technical skills evaluations. There was considerable variability in the times to completion of critical intervention, particularly for control of cardiac and vascular injuries.

Conclusion: Initial evaluations support the use of this novel perfused cadaver model for the training and evaluation of military FSTs. Preliminary data highlight the utility for open vascular, thoracic, and other high-acuity/low-volume procedures critical to combat casualty care. Larger studies are needed for model optimization and further validation of an objective structured technical assessment tool.

Level of evidence: Care management, level V.

Ketamine as an Anesthetic for Patients with Acute Brain Injury: A Systematic Review

Mads Christian Tofte Gregers, Søren Mikkelsen, Katrine Prier Lindvig, Anne Craveiro Brøchner

Neurocrit Care 2020 Aug;33(1):273-282 

For years, the use of ketamine as an anesthetic to patients suffering from acute brain injury has been debated because of its possible deleterious effects on the cerebral circulation and thus on the cerebral perfusion. Early studies suggested that ketamine could increase the intracranial pressure thus lowering the cerebral perfusion and hence reduce the oxygen supply to the injured brain. However, more recent studies are less conclusive and might even indicate that patients with acute brain injury could benefit from ketamine sedation. This systematic review summarizes the evidence regarding the use of ketamine in patients suffering from traumatic brain injury. Databases were searched for studies using ketamine in acute brain injury.

Outcomes of interest were mortality, intracranial pressure, cerebral perfusion pressure, blood pressure, heart rate, spreading depolarizations, and neurological function. In total 11 studies were included. The overall level of evidence concerning the use of ketamine in brain injury is low. Only two studies found a small increase in intracranial pressure, while two small studies found decreased levels of intracranial pressure following ketamine administration. We found no evidence of harm during ketamine use in patients suffering from acute brain injury.

Right Patient, Right Place, Right Time : Field Triage and Transfer to Level I Trauma Centers

Benjamin L Gough, Matthew D Painter, Autumn L Hoffman, Richard J Caplan, Cynthia A Peters, Mark D Cipolle 

Am Surg. 2020 Dec;86(12):1697-1702 

Introduction: This study sought to compare outcomes of trauma patients taken directly from the field to a Level I trauma center (direct) versus patients that were first brought to a Level III trauma center prior to being transferred to a Level I (transfer) within our inclusive Delaware trauma system. 

Methods: A retrospective review of the Level I center's trauma registry was performed using data from 2013 to 2017 for patients brought to a single Level I trauma center from 2 surrounding counties. The direct cohort consisted of 362 patients, while the transfer cohort contained 204 patients. Linear regression analysis was performed to investigate hospital length of stay (LOS), while logistic regression was used for mortality, complications, and craniotomy. Covariates included age, gender, county, and injury severity score (ISS). Propensity score weighting was also performed between the direct and transfer cohorts. 

Results: When adjusting for age, gender, ISS, and county, transferred patients demonstrated worse outcomes compared with direct patients in both the regression and propensity score analyses. Transferred patients were at increased risk of mortality (odds ratio [OR] 2.17, CI 1.10-4.37, P = .027) and craniotomy (OR 3.92, CI 1.87-8.72, P < .001). Age was predictive of mortality (P < .001). ISS was predictive of increased risk of mortality (P < .001), increased LOS (P < .001), and craniotomy (P < .001). Older age, Sussex County, and higher ISS were predictive of patients being transferred (P < .001). 

Discussion: Delays in the presentation to our Level I trauma center resulted in worse outcomes. Patients that meet criteria should be considered for transport directly to the highest level trauma center in the system to avoid delays in care.

 

Trauma-Induced Coagulopathy and Massive Bleeding: Current Hemostatic Concepts and Treatment Strategies

Johannes Gratz, Daniel Oberladstätter, Herbert Schöchl 

Hamostaseologie. 2020 Sep 7. doi: 10.1055/a-1232-7721 

Hemorrhage after trauma remains a significant cause of preventable death. Trauma-induced coagulopathy (TIC) at the time of hospital admission is associated with an impaired outcome. Rather than a universal phenotype, TIC represents a complex hemostatic disorder, and standard coagulation tests are not designed to adequately reflect the complexity of TIC. Viscoelastic testing (VET) has gained increasing interest for the characterization of TIC because it provides a more comprehensive depiction of the coagulation process. Thus, VET has been established as a point-of-care-available hemostatic monitoring tool in many trauma centers. Damage-control resuscitation and early administration of tranexamic acid provide the basis for treating TIC. To improve survival, ratio-driven massive transfusion protocols favoring early and high-dose plasma transfusion have been implemented in many trauma centers around the world. Although plasma contains all coagulation factors and inhibitors, only high-volume plasma transfusion allows for adequate substitution of lacking coagulation proteins. However, high-volume plasma transfusion has been associated with several relevant risks. In some European trauma facilities, a more individualized hemostatic therapy concept has been implemented. The hemostatic profile of the bleeding patient is evaluated by VET. Subsequently, goal-directed hemostatic therapy is primarily based on coagulation factor concentrates such as fibrinogen concentrate or prothrombin complex concentrate. However, a clear difference in survival benefit between these two treatment strategies has not yet been shown. This concise review aims to summarize current evidence for different diagnostic and therapeutic strategies in patients with TIC.

Prehospital Management of Traumatic Brain Injury across Europe: A CENTER-TBI Study 

Benjamin Yaël Gravesteijn, Charlie Aletta Sewalt, Nino Stocchetti, Giuseppe Citerio, Ari Ercole, Hester Floor Lingsma, Nicole von Steinbüchel, Ewout Willem Steyerberg, Lindsay Wilson, Andrew I R Maas, David K Menon, Fiona Elizabeth Lecky, CENTER-TBI collaborators 

Prehosp Emerg Care. 2020 Oct 1;1-15. doi: 10.1080/10903127.2020.1817210. Online ahead of print. 

Background: Prehospital care for traumatic brain injury (TBI) is important to prevent secondary brain injury. We aim to compare prehospital care systems within Europe and investigate the association of system characteristics with the stability of patients at hospital arrival. 

Methods: We studied TBI patients who were transported to CENTER-TBI centers, a pan-European, prospective TBI cohort study, by emergency medical services between 2014 and 2017. The association of demographic factors, injury severity, situational factors, and interventions associated with on-scene time was assessed using linear regression. We used mixed effects models to investigate the case mix adjusted variation between countries in prehospital times and interventions. The case mix adjusted impact of on-scene time and interventions on hypoxia (oxygen saturation <90%) and hypotension (systolic blood pressure <100mmHg) at hospital arrival was analyzed with logistic regression. 

Results: Among 3878 patients, the greatest driver of longer on-scene time was intubation (+8.3 min, 95% CI: 5.6-11.1). Secondary referral was associated with shorter on-scene time (-5.0 min 95% CI: -6.2- -3.8). Between countries, there was a large variation in response (range: 12-25 min), on-scene (range: 16-36 min) and travel time (range: 15-32 min) and in prehospital interventions. These variations were not explained by patient factors such as conscious level or severity of injury (expected OR between countries: 1.8 for intubation, 1.8 for IV fluids, 2.0 for helicopter). On-scene time was not associated with the regional EMS policy (p= 0.58). Hypotension and/or hypoxia were seen in 180 (6%) and 97 (3%) patients in the overall cohort and in 13% and 7% of patients with severe TBI (GCS <8). The largest association with secondary insults at hospital arrival was with major extracranial injury: the OR was 3.6 (95% CI: 2.6-5.0) for hypotension and 4.4 (95% CI: 2.9-6.7) for hypoxia. 

Discussion: Hypoxia and hypotension continue to occur in patients who suffer a TBI, and remain relatively common in severe TBI. Substantial variation in prehospital care exists for patients after TBI in Europe, which is only partially explained by patient factors.

Tracheal intubation in traumatic brain injury: a multicentre prospective observational study

Benjamin Yael Gravesteijn, Charlie Aletta Sewalt, Daan Nieboer, David Krishna Menon, Andrew Maas, Fiona Lecky, Markus Klimek, Hester Floor Lingsma, CENTER-TBI collaborators 

Br J Anaesth. 2020 Oct;125(4):505-517 

Background: We aimed to study the associations between pre- and in-hospital tracheal intubation and outcomes in traumatic brain injury (TBI), and whether the association varied according to injury severity. 

Methods: Data from the international prospective pan-European cohort study, Collaborative European NeuroTrauma Effectiveness Research for TBI (CENTER-TBI), were used (n=4509). For prehospital intubation, we excluded self-presenters. For in-hospital intubation, patients whose tracheas were intubated on-scene were excluded. The association between intubation and outcome was analysed with ordinal regression with adjustment for the International Mission for Prognosis and Analysis of Clinical Trials in TBI variables and extracranial injury. We assessed whether the effect of intubation varied by injury severity by testing the added value of an interaction term with likelihood ratio tests. 

Results: In the prehospital analysis, 890/3736 (24%) patients had their tracheas intubated at scene. In the in-hospital analysis, 460/2930 (16%) patients had their tracheas intubated in the emergency department. There was no adjusted overall effect on functional outcome of prehospital intubation (odds ratio=1.01; 95% confidence interval, 0.79-1.28; P=0.96), and the adjusted overall effect of in-hospital intubation was not significant (odds ratio=0.86; 95% confidence interval, 0.65-1.13; P=0.28). However, prehospital intubation was associated with better functional outcome in patients with higher thorax and abdominal Abbreviated Injury Scale scores (P=0.009 and P=0.02, respectively), whereas in-hospital intubation was associated with better outcome in patients with lower Glasgow Coma Scale scores (P=0.01): in-hospital intubation was associated with better functional outcome in patients with Glasgow Coma Scale scores of 10 or lower. 

Conclusion: The benefits and harms of tracheal intubation should be carefully evaluated in patients with TBI to optimise benefit. This study suggests that extracranial injury should influence the decision in the prehospital setting, and level of consciousness in the in-hospital setting.

Prehospital plasma is associated with distinct biomarker expression following injury

Danielle S Gruen, Joshua B Brown, Francis X Guyette 3, Yoram Vodovotz, Pär I Johansson, Jakob Stensballe, Derek A Barclay, Jinling Yin, Brian J Daley, Richard S Miller, Brian G Harbrecht, Jeffrey A Claridge, Herb A Phelan, Matthew D Neal, Brian S Zuckerbraun, Timothy R Billiar, Jason L Sperry, PAMPer study group

JCI Insight 2020 Apr 23;5(8):e135350 

BACKGROUND: Prehospital plasma improves survival in severely injured patients transported by air ambulance. We hypothesized that prehospital plasma would be associated with a reduction in immune imbalance and endothelial damage.

METHODS: We sampled blood from 405 trauma patients enrolled in the Prehospital Air Medical Plasma (PAMPer) trial upon hospital admission (0 hours) and 24 hours post admission across 6

U.S. sites. We assayed samples for 21 inflammatory mediators and 7 markers associated with endothelial function and damage. We performed hierarchical clustering analysis (HCA) of these biomarkers of the immune response and endothelial injury. Regression analysis was used to control for differences across study and to assess any association with prehospital plasma resuscitation.

RESULTS: HCA distinguished two patient clusters with different injury patterns and outcomes. Patients in cluster A had greater injury severity and incidence of blunt trauma, traumatic brain injury, and mortality. Cluster A patients that received prehospital plasma showed improved 30- day survival. Prehospital plasma did not improve survival in cluster B patients. In an adjusted analysis of the most seriously injured patients, prehospital plasma was associated with an increase in adiponectin, IL-1β, IL-17A, IL-23, and IL-17E upon admission, and a reduction in syndecan-1, TM, VEGF, IL-6, IP-10, MCP-1, and TNF-α, and an increase in IL-33, IL-21, IL-23, and IL-17E 24 hours later.

CONCLUSION: Prehospital plasma may ameliorate immune dysfunction and the endotheliopathy of trauma. These effects of plasma may contribute to improved survival in injured patients.

TRIAL REGISTRATION: NCT01818427.

FUNDING: Department of Defense; National Institutes of Health, U.S. Army.

CHARACTERIZATION OF UNEXPECTED SURVIVORS FOLLOWING A PREHOSPITAL PLASMA RANDOMIZED TRIAL 

Danielle S Gruen, Frank X Guyette, Joshua B Brown, Brian J Daley, Richard S Miller, Brian G Harbrecht, Jeffrey A Claridge, Herb A Phelan, Mark H Yazer, Matthew D Neal, Brian S Zuckerbraun, Jason L Sperry

J Trauma Acute Care Surg 2020 May 27;Online ahead of print. 

Background: Prehospital plasma improves survival for severely injured trauma patients transported by air ambulance. We sought to characterize the unexpected survivors, patients who survived despite having high predicted mortality following traumatic injury.

Methods: The Prehospital Air Medical Plasma (PAMPer) trial randomized severely injured patients (n=501) to receive either standard care (crystalloid) or two units of prehospital plasma followed by standard care fluid resuscitation. We built a generalized linear model to estimate patient mortality. Area under the receiver operating characteristic curve (AUC) was used to evaluate model performance. We defined unexpected survivors as patients who had a predicted mortality >50% and survived to 30 days. We characterized patient demographics, clinical features, and outcomes of the unexpected survivors. Observed to expected (O/E) ratios and Z- statistics were calculated using model-estimated mortality for each cohort.

Results: Our model predicted mortality better than ISS or RTS parameters and identified 36 unexpected survivors. Compared to expected survivors, unexpected survivors were younger (33 [24, 52] vs. 47 [32, 59] years, P=0.013), were more severely injured (ISS 34 [22, 50] vs. 18 [10, 27], P<0.001), had worse organ dysfunction and hospital resource outcomes (MOF, ICU and hospital length of stay, and ventilator days), and were more likely to receive prehospital plasma (67 vs. 46%, P=0.031). Nonsurvivors with high predicted mortality were more likely to receive standard care resuscitation (P<0.001). Unexpected survivors who received prehospital plasma had a lower observed to expected mortality than those that received standard care resuscitation (O/E 0.56 [0.33-0.84] vs. 1.0 [0.73-1.32]). The number of prehospital plasma survivors (24) exceeded the number of predicted survivors (n=10) estimated by our model (P<0.001).

Conclusions: Prehospital plasma is associated with an increase in the number of unexpected survivors following severe traumatic injury. Prehospital interventions may improve the probability of survival for injured patients with high predicted mortality based on early injury characteristics, vital signs, and resuscitation measures.Secondary Analysis LEVEL OF EVIDENCE: II.

Association of Prehospital Plasma With Survival in Patients With Traumatic Brain Injury: A Secondary Analysis of the PAMPer Cluster Randomized Clinical Trial

Danielle S Gruen, Francis X Guyette, Joshua B Brown, David O Okonkwo, Ava M Puccio, Insiyah K Campwala, Matthew T Tessmer, Brian J Daley, Richard S Miller, Brian G Harbrecht, Jeffrey A Claridge, Herb A Phelan, Matthew D Neal, Brian S Zuckerbraun, Mark H Yazer, Timothy R Billiar, Jason L Sperry

JAMA Netw Open. 2020 Oct 1;3(10):e2016869. doi: 10.1001/jamanetworkopen.2020.16869.

Importance: Prehospital plasma administration improves survival in injured patients at risk for hemorrhagic shock and transported by air ambulance. Traumatic brain injury (TBI) is a leading cause of death following trauma, but few early interventions improve outcomes.

Objective: To assess the association between prehospital plasma and survival in patients with TBI.

Design, setting, and participants: The Prehospital Air Medical Plasma (PAMPer) trial was a pragmatic, multicenter, phase 3, cluster randomized clinical trial involving injured patients who were at risk for hemorrhagic shock during air medical transport to a trauma center. The trial was conducted at 6 US sites with 9 level-I trauma centers (comprising 27 helicopter emergency services bases). The original trial analyzed 501 patients, including 230 patients who were randomized to receive plasma and 271 randomized to standard care resuscitation. This secondary analysis of a predefined subgroup included patients with TBI. Data analysis was performed from October 2019 to February 2020.

Interventions: Patients were randomized to receive standard care fluid resuscitation or 2 units of thawed plasma.

Main outcomes and measures: The primary outcome was mortality at 30 days. Patients with TBI were prespecified as a subgroup for secondary analysis and for measurement of markers of brain injury. The 30-day survival benefit of prehospital plasma in subgroups with and without TBI as diagnosed by computed tomography was characterized using Kaplan-Meier survival analysis and Cox proportional hazard regression.

Results: In total, 166 patients had TBI (median [interquartile range] age, 43.00 [25.00-59.75] years; 125 men [75.3%]). When compared with the 92 patients who received standard care, the 74 patients with TBI who received prehospital plasma had improved 30-day survival even after adjustment for multiple confounders and assessment of the degree of brain injury with clinical variables and biomarkers (hazard ratio [HR], 0.55; 95% CI, 0.33-0.94; P = .03). Receipt of prehospital plasma was associated with improved survival among patients with TBI with a prehospital Glasgow Coma Scale score of less than 8 (HR, 0.56; 95% CI, 0.35-0.91) and those with polytrauma (HR, 0.50; 95% CI, 0.28-0.89). Patients with TBI transported from the scene of injury had improved survival following prehospital plasma administration (HR, 0.45; 95% CI, 0.26-0.80; P = .005), whereas patients who were transferred from an outside hospital showed no difference in survival for the plasma intervention (HR, 1.00; 95% CI, 0.33-3.00; P = .99).

Conclusions and relevance: These findings are exploratory, but they suggest that receipt of prehospital plasma is associated with improved survival in patients with computed tomography-positive TBI. The prehospital setting may be a critical period to intervene in the care of patients with TBI. Future studies are needed to confirm the clinical benefits of early plasma resuscitation following TBI and concomitant polytrauma.

Fixed Wing Tactical Aircraft for Air Medical Evacuation in Sahel

Pierre Guénot, Vincent Beauchamps, Samuel Madec, Cyril Carfantan, Mathieu Boutonnet, Laura Bareau, Hélène Romain, Stéphane Travers

Air Med J Sep-Oct 2019;38(5):350-355 

Abstract

Objective: The medical support of military operations over a 5 million km2 area in the Sahel- Saharan strip has justified the use of a medical fixed wing aircraft. Two CASA CN 235 aircraft currently perform medical evacuation (medevac) from the point of injury to forward surgical structures and then to the international airport before strategic medevac to France.

Methods: A retrospective observational study including all flights performed from January 2013 to December 2017 by the medical CASA located in Mali.

Results: Three thousand three flight hours were achieved. Four hundred twenty-four medevacs were performed for 898 patients. Seventy-five percent were evacuated from forward surgical structures. Their initial categorization included 10% Alpha, 23% Bravo, and 67% Charlie.

Mechanical ventilation was performed for 5%; 34.5% had common medical or surgical pathologies, 34.2% were combat casualties mostly by explosion, and 18.7% were nonbattle injuries. No difficulties related to the aeronautical environment were reported by the teams.

Conclusion: Tactical medevac with fixed wing aircraft has become a crucial link in the French medical evacuation chain in remote areas. Military emergency medical teams were able to provide in-flight intensive care before and after damage control surgery. Discussions are underway to consider possible doctrinal and logistical evolutions.

Emergency Care Provided by the Israeli Military Airborne Combat Evacuation Unit during Helicopter Winch Rescue Operations

Ariel Guinzburg, Danny Epstein, Jonathan Cohen, Shai Kiso, Eliad Aviram, Shachar Shapira, Itai Shavit 1, Asaf Miller

Prehosp Emerg Care. 2020 May 1; Online ahead of print 

Objectives: The objective of this study was to evaluate the emergency care provided by the Israeli Military Airborne Combat Evacuation Unit (MACEU) during helicopter winching operations.

Methods: A retrospective cohort study was performed of all patients rescued by winching by the MACEU between December 2011 and October 2018. Data were extracted from the electronic medical records of the unit registry. The data collected included helicopter type, scene times, demographics, mechanism of injury, interventions, medications, and survival.

Results: During the study period, 208 civilians with a mean age of 36.8 ± 19.2 years were evacuated from inaccessible areas, 192 were from difficult terrain, 10 from sea vessels, and 5 from floods. All patients were winched up with a crewmember. No patient or crewmember was injured during winching. Overall, 156/208 (75%) had a traumatic injury, and 52/208 (25%) had a medical emergency. Sikorsky UH-60 "BlackHawk" helicopters and Sikorsky CH-53 "Sea Stallion" helicopters were used in 179 and 28 operations, respectively. Eighteen different procedures were performed by the medical personnel of the unit on scene and en route. The most performed procedures were peripheral vascular access establishment (60.6%), fluids administration (57.7%), oxygen supplementation (42.8%), analgesia (39.9%) and spine immobilization (37.5%). On scene, none of the patients was treated with a physician-only intervention. Thirty/208 (14.5%) patients were winched-up in darkness conditions. Eleven/208 (5.3%) apneic breathing patients were winched up ventilated by a crewmember. All the six patients who had oxygen saturation ≥89% after entrance into the cabin, survived.

Conclusions: The reported MACEU experience provides useful information on the clinical characteristics, medical interventions, and outcomes of patients rescued using a winching operation. Study findings emphasize the importance of airway management and ventilation during winching.

Maintaining Surgical Readiness While Deployed to Low-Volume Military Treatment Facilities: A Pilot Program for Clinical and Operational Sustainment Training in the Deployed Environment

Jennifer M Gurney, Will C Cole, John C Graybill, Stacy A Shackelford, Darin K Via Mil Med 2020 Jan 7;185(Suppl 1):508-512 

Introduction: Maintaining readiness among Army surgeons is increasingly challenging because of declining operative experience during certain deployments. Novel solutions should be considered.

Materials and methods: A pilot program was conducted to rotate surgical teams from a military treatment facility with a low volume of combat casualty care to one with a higher volume. Pre- and postrotation surveys were conducted to measure relative operative experience, trauma experience, and perceived readiness among rotators.

Results: Operative volumes and trauma volumes were increased and that perceived readiness among rotators, especially those with the fewest previous deployments, was improved.

Conclusions: Maintaining readiness among Army surgeons is a difficult task, but a combination of increased trauma care while in garrison, as well as increased humanitarian care during deployments, may be helpful. Additionally, rotating providers from facilities caring for few combat casualties to facilities caring for more combat casualties may also be feasible, safe, and helpful.

Improved survival in critically injured combat casualties treated with fresh whole blood by forward surgical teams in Afghanistan

Jennifer Gurney, Amanda Staudt, Andrew Cap, Stacy Shackelford, Elizabeth Mann- Salinas, Tuan Le, Shawn Nessen, Philip Spinella

Transfusion 2020 Jun;60 Suppl 3:S180-S188 

Background: The objective of this study was to assess transfusion strategies and outcomes, stratified by the combat mortality index, of casualties treated by small surgical teams in Afghanistan. Resuscitation that included warm fresh whole blood (FWB) was compared to blood component resuscitation.

Study design and methods: Casualties treated by a Role 2 surgical team in Afghanistan from 2008 to 2014 who received 1 or more units of red blood cells (RBCs) or FWB were included.

Patients were excluded if they had incomplete data or length of stay less than 30 minutes. Patients were separated into two groups: 1) received FWB and 2) did not receive FWB; moreover, both groups potentially received plasma, RBCs, and platelets. The analysis was stratified by critically versus noncritically injured patients using the prehospital combat mortality index. Kaplan-Meier plot, log-rank test, and multivariable Cox regression were performed to compare survival.

Results: In FWB patients, median units of FWB and total blood product were 4.0 (interquartile range [IQR], 2.0-7.0) and 16.0 (IQR, 10.0-28.0), respectively. The Kaplan-Meier plot demonstrated that survival was similar between FWB (79.1%) and no-FWB (74.5%) groups (p = 0.46); after stratifying patients by the combat mortality index, the risk of mortality was increased in the no-FWB group (hazard ratio, 2.8; 95% confidence interval, 1.2-6.4) compared to the FWB cohort.

Conclusion: In forward-deployed environments, where component products are limited, FWB has logistical advantages and was associated with reduced mortality in casualties with a critical combat mortality index. Additional analysis is needed to determine if these effects of FWB are appreciable in all trauma patients or just in those with severe physiologic derangement.

Tactical Combat Casualty Care Training, Knowledge, and Utilization in the US Army

 Jennifer M Gurney, Caryn A Stern, Russ S Kotwal, Cord W Cunningham, Dallas R Burelison, Kirby R Gross, Harold R Montgomery, Edward H Whitt, Clinton K Murray, Zsolt T Stockinger, Frank K Butler, Stacy A Shackelford

Mil Med 2020 Jan 7;185(Suppl 1):500-507 

Abstract

Introduction: Tactical Combat Casualty Care (TCCC) is the execution of prehospital trauma skills in the combat environment. TCCC was recognized by the 2018 Department of Defense Instruction on Medical Readiness Training as a critical wartime task. This study examines the training, understanding, and utilization of TCCC principles and guidelines among US Army medical providers and examines provider confidence of medics in performing TCCC skills.

Materials and methods: A cross-sectional survey, developed by members of the Committee on TCCC, was distributed to all US Army Physicians and Physician Assistants via anonymous electronic communication.

Results: A total of 613 completed surveys were included in the analyses. Logistic regression analyses were conducted on: TCCC test score of 80% or higher, confidence with medic utilization of TCCC, and medic utilization of ketamine in accordance with TCCC.

Conclusions: <60% of respondents expressed confidence in the ability of the medics to perform all TCCC skills. Supervising providers who that believed 80 to 100% of their medics had completed TCCC training had more confidence in their medic's TCCC abilities. With TCCC, a recognized lifesaver on the battlefield, continued training and utilization of TCCC concepts are paramount for deploying personnel.

The Prehospital Evaluation and Care of Moderate/Severe TBI in the Austere Environment

Jennifer M Gurney, Paul E Loos, Mayumi Prins, David W Van Wyck, Randall R McCafferty, Donald W Marion

Mil Med 2020 Jan 7;185(Suppl 1):148-153

 Abstract

Increased resource constraints secondary to a smaller medical footprint, prolonged evacuation times, or overwhelming casualty volumes all increase the challenges of effective management of traumatic brain injury (TBI) in the austere environment. Prehospital providers are responsible for the battlefield recognition and initial management of TBI. As such, targeted education is critical to efficient injury recognition, promoting both provider readiness and improved patient outcomes. When austere conditions limit or prevent definitive treatment, a comprehensive understanding of TBI pathophysiology can help inform acute care and enhance prevention of secondary brain injury. Field deployable, noninvasive TBI assessment and monitoring devices are urgently needed and are currently undergoing clinical evaluation. Evidence shows that the assessment, monitoring, and treatment in the first few hours and days after injury should focus on the preservation of cerebral perfusion and oxygenation. For cases where medical management is inadequate (eg, evidence of an enlarging intracranial hematoma), guidelines have been developed for the performance of cranial surgery by nonneurosurgeons. TBI management in the austere environment will continue to be a challenge, but research focused on improving evidence-based monitoring and therapeutic interventions can help to mitigate some of these challenges and improve patient outcomes.

A Blended Prehospital Ultrasound Curriculum for Critical Care Paramedics

Andrew Guy, Anthony Bryson, Stephen Wheeler, Neilson McLean, Hussein D Kanji Air Med J Nov-Dec 2019;38(6):426-430

Abstract

Objective: Point-of-care ultrasound is a nascent and growing area of prehospital care. Most previously described ultrasound curricula for paramedics examine a single type of ultrasound scan. Here, we describe the implementation and evaluation of a prehospital ultrasound curriculum using a blended model of traditional didactics and hands-on experience with online prereading.

Methods: We recruited a prospective convenience sample of critical care paramedics without prior ultrasound experience to take part in a 2-day ultrasound course. All participants completed prereading modules built from online resources followed by a didactic review of the material and hands-on practice. Ultrasound examinations included extended focused abdominal sonography in trauma, cardiac ultrasound, thoracic ultrasound, and vascular ultrasound. A written examination evaluated ultrasound theory and image interpretation, and a practical examination evaluated image acquisition.

Results: Seventeen critical care paramedics completed the course with a mean grade on the written examination of 76%, with 76% of paramedics achieving the predetermined passing mark of 70% or greater. All paramedics passed the practical examination.

Conclusion: The implementation of a prehospital critical care ultrasound program is feasible in our provincial emergency medical services system. Further assessment is necessary to determine future knowledge and skill retention as well as clinical application and utility in real- world settings.

Tranexamic Acid During Prehospital Transport in Patients at Risk for Hemorrhage After Injury: A Double-blind, Placebo-Controlled, Randomized Clinical Trial

 Francis X Guyette, Joshua B Brown, Mazen S Zenati, Barbara J Early-Young, Peter W Adams, Brian J Eastridge, Raminder Nirula, Gary A Vercruysse, Terence O'Keeffe, Bellal Joseph, Louis H Alarcon, Clifton W Callaway, Brian S Zuckerbraun, Matthew D Neal, Raquel M Forsythe, Matthew R Rosengart, Timothy R Billiar, Donald M Yealy, Andrew B Peitzman, Jason L Sperry, STAAMP Study Group 

JAMA Surg. 2020 Oct 5;156(1):11-20 

Importance: In-hospital administration of tranexamic acid after injury improves outcomes in patients at risk for hemorrhage. Data demonstrating the benefit and safety of the pragmatic use of tranexamic acid in the prehospital phase of care are lacking for these patients. 

Objective: To assess the effectiveness and safety of tranexamic acid administered before hospitalization compared with placebo in injured patients at risk for hemorrhage. 

Design, setting, and participants: This pragmatic, phase 3, multicenter, double-blind, placebo-controlled, superiority randomized clinical trial included injured patients with prehospital hypotension (systolic blood pressure ≤90 mm Hg) or tachycardia (heart rate ≥110/min) before arrival at 1 of 4 US level 1 trauma centers, within an estimated 2 hours of injury, from May 1, 2015, through October 31, 2019. 

Interventions: Patients received 1 g of tranexamic acid before hospitalization (447 patients) or placebo (456 patients) infused for 10 minutes in 100 mL of saline. The randomization scheme used prehospital and in-hospital phase assignments, and patients administered tranexamic acid were allocated to abbreviated, standard, and repeat bolus dosing regimens on trauma center arrival. 

Main outcomes and measures: The primary outcome was 30-day all-cause mortality. 

Results: In all, 927 patients (mean [SD] age, 42 [18] years; 686 [74.0%] male) were eligible for prehospital enrollment (460 randomized to tranexamic acid intervention; 467 to placebo intervention). After exclusions, the intention-to-treat study cohort comprised 903 patients: 447 in the tranexamic acid arm and 456 in the placebo arm. Mortality at 30 days was 8.1% in patients receiving tranexamic acid compared with 9.9% in patients receiving placebo (difference, -1.8%; 95% CI, -5.6% to 1.9%; P = .17). Results of Cox proportional hazards regression analysis, accounting for site, verified that randomization to tranexamic acid was not associated with a significant reduction in 30-day mortality (hazard ratio, 0.81; 95% CI, 0.59-1.11, P = .18). Prespecified dosing regimens and post-hoc subgroup analyses found that prehospital tranexamic acid were associated with significantly lower 30-day mortality. When comparing tranexamic acid effect stratified by time to treatment and qualifying shock severity in a post hoc comparison, 30-day mortality was lower when tranexamic acid was administered within 1 hour of injury (4.6% vs 7.6%; difference, -3.0%; 95% CI, -5.7% to -0.3%; P < .002). Patients with severe shock (systolic blood pressure ≤70 mm Hg) who received tranexamic acid demonstrated lower 30-day mortality compared with placebo (18.5% vs 35.5%; difference, -17%; 95% CI, -25.8% to -8.1%; P < .003). 

Conclusions and relevance: In injured patients at risk for hemorrhage, tranexamic acid administered before hospitalization did not result in significantly lower 30-day mortality. The prehospital administration of tranexamic acid after injury did not result in a higher incidence of thrombotic complications or adverse events. Tranexamic acid given to injured patients at risk for hemorrhage in the prehospital setting is safe and associated with survival benefit in specific subgroups of patients.

Estimates of Total Burned Surface Area by Emergency Department Clinicians and Burn Specialists

 Barry Hahn, Seungwhan Alex Roh, Christopher Price, Wayne Fu, Jaclyn Dibello, Nicole Berwald, Josh Greenstein, Jerel Chacko 

Cureus. 2020 Jul 23;12(7):e9362. doi: 10.7759/cureus.9362 

Abstract 

Introduction Correctly assessing burn size is extremely important since it is directly associated with a patient's subsequent management. Further, an accurate assessment of the total body surface area (TBSA) involved is crucial to decide if specialty care in a burn unit is necessary, whereby overestimation has the potential to lead to unnecessary patient transfers and undesirable burdens on the healthcare system and inconvenience to patients. The goal of this study was to identify whether burn injury estimates of TBSA percentage correlate between emergency department (ED) clinician and burn specialists. Methods This was a retrospective study conducted between February 1, 2018 and July 31, 2019 of patients with a burn injury who were evaluated by both an ED clinician and a burn specialist during the same ED visit. Charts were reviewed to identify the documentation of TBSA by pre-hospital personnel, ED nursing staff, ED mid-level providers (MLP), ED attending physicians, burn consultant MLPs, and burn consultant attending physicians. Results During the study period, 189 subjects with both an ED and burn consultant. The median age was 11 years [interquartile range (IQR) 1-49], and 103 (54%) were males. More than half of the subjects (n=106, 56%) were under the age of 18. There was a statistically significant correlation between estimates of TBSA between ED and burn consultants overall (p<0.0001). Furthermore, there was a statistically significant correlation between ED and burn MLPs (p<0.0001) as well as ED and burn attending physicians (p<0.0001). When adjusted for MLP and attending sex, there was still a correlation among all groups (p<0.0001). Conclusions In this study, there was a statistically significant correlation between estimates of TBSA between ED and burn consultants.

Patient Transportation Delays and Effects on Operation Theatres' Efficiency: A Study for Problem Analysis and Remedial Measures

Rudrashish Haldar, Devendra Gupta, Hemchandra Pandey, Shashi Srivastava, Prabhakar Mishra, Anil Agarwal

Anesth Essays Res Jul-Sep 2019;13(3):554-559 

Abstract

Background and aims: Delay in patients' transportation to the operating theater (OT) is a globally recognized phenomenon, leading to delay in the subsequent processes (anesthesia induction, surgery, and patient turnover). This observational study was conducted to evaluate the common reasons for delay in transporting patients to the neurosurgery OT complex and its consequent effects and how the elimination of these reasons by application of feasible measures can influence the after effects.

Settings and design: This was an anesthesiologist-based audit of transportation process of patients to the OT complex of a tertiary care teaching hospital to identify the impediments and effects of delay, suggest and implement remedial measures, and assess the outcomes.

Materials and methods: The movement process of successive 551 patients was studied. In the evaluation phase, common reasons for transportation delays were identified. The incidences of consequent effects such as second-case cancellations and overrunning of OTs beyond scheduled hours were noted. In the implementation phase, corrective measures were instituted and the incidences of delays and the consequent effects were again noted.

Statistical analysis: Statistical analysis was performed using SPSS 17.0.

Results: In the evaluation phase (303 patients), common reasons for delays included porter- associated delays (15), unavailable lifts (7), and pediatric patients (6). The incidences of case cancellation (20) and overrunning of OTs (9) were high. In the implementation phase, after remedial measures were enforced, the incidences of delays due to porter, lifts, and pediatric patients dropped to 1, 6, and 0, respectively. Simultaneously, a decrease in second-case cancellation (2) and overrunning of OTs (7) also reduced. As an additional finding, a significant reduction in OT turnover times was also observed (16.31 ± 9.29 min vs. 11.70 ± 5.78 min).

Conclusions: Analysis of common reasons of patient transportation delays and removal of these impediments can markedly improve the efficiency in OT functioning.

Initial blood pressure is important for long-term outcome after traumatic spinal cord injury

Mette Haldrup, Stig Dyrskog, Mathias Møller Thygesen, Hans Kirkegaard, Helge Kasch, Mikkel Mylius Rasmussen

J Neurosurg Spine 2020 Mar 20;1-5;Online ahead of print. 

Objective: Patients with traumatic spinal cord injury (TSCI) are at risk of developing neurogenic shock that causes hypotension and thereby secondary injury to the spinal cord due to ischemia. Hemodynamic treatment of patients with acute TSCI remains inadequately elucidated.

Guidelines for management are divergent and based on limited evidence. To this end, the authors evaluated whether mean arterial blood pressure (MABP) during the prehospital and initial hospital phases of TSCI treatment is correlated with long-term neurological outcome.

Methods: The authors performed a retrospective cohort study based on a chart review of MABP data collected during the prehospital transport, in the operating room (OR), and in the neurointensive care unit (NICU) during the first 7 days after trauma. Data from the NICU were divided into two periods: days 1-2 and days 3-7. Data were analyzed using Spearman's rank correlation to evaluate for any correlation between MABP and changes in the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) score 1 year postinjury. In the analysis, the MABP target value was 80 mm Hg. Hypotension was treated with metaoxedrin or norepinephrine. Statistically significant differences were evaluated using Spearman's rank correlation coefficient.

Results: The chart review yielded 129 patients treated for TSCI. The inclusion period was 2010-2017. For the prehospital transport measurements of MABP, the Spearman's rank correlation coefficient was a rho of 0.5662 (p < 0.001), for OR measurements it was a rho of 0.6818 (p < 0.001), and for the NICU measurements it was a rho of 0.4611 (p < 0.001); for NICU unit days 1-2 and days 3-7, the Spearman's rank correlation coefficient was a rho of 0.2209 (p = 0.0681).

Conclusions: Continuous MABP levels exceeding 80 mm Hg have a significant impact on neurological outcome-from earliest possible stabilization in the prehospital care, through hospital admission, the surgical phase, and into the first 2 days in the NICU..

Ketamine Use for Prolonged Field Care Reduces Supply Use

 Andrew B Hall, Lindsay Morrow, Michael Dixon 

J Spec Oper Med. Fall 2020;20(3):120-121 

Abstract 

This case describes the prolonged treatment of a 38-year-old man with a transpelvic gunshot wound requiring a diverting ostomy and cystostomy for damage control procedures with a comminuted acetabular and femoral head fracture. The team used a ketamine drip for prolonged field care over 48 hours. The benefit of using a ketamine drip included low supply requirement, excellent analgesia, and ease of administration, but side-effects included somnolence and atelectasis necessitating oxygen supplementation before evacuation.

Strategies to improve communication in telementoring in acute care coordination: a scoping review

 Lauren Hampton, Peter Brindley, Andrew Kirkpatrick, Jessica McKee, Julian Regehr, Douglas Martin, Anthony LaPorta, Jason Park, Ashley Vergis, Lawrence Gillman 

Can J Surg. 2020 Nov 30;63(6):E569-E577 

Background: Telementoring facilitates the coordination of advanced medical care in rural, remote or austere environments. Because the interpersonal element of telementoring has been relatively underexplored, we conducted a scoping review to identify strategies to improve communication in telementoring. 

Methods: Two independent reviewers searched all English-language articles in MEDLINE and Scopus from 1964 to 2017, as well as reference lists of relevant articles to identify articles addressing telementored interactions between health care providers. Search results were gathered in June 2017 and updated in January 2018. Identified articles were categorized by theme. 

Results: We identified 144 articles, of which 56 met our inclusion criteria. Forty-one articles focused on improving dispatcher-directed cardiopulmonary resuscitation (CPR). Major themes included the importance of language in identifying out-of-hospital cardiac arrest and how to provide instructions to enable administration of effective CPR. A standardized approach with scripted questions was associated with improved detection of out-of-hospital cardiac arrest, and a concise script was associated with improved CPR quality compared to no mentoring, unscripted mentoring or more complex instructions. Six articles focused on physician-physician consultation. Use of a handover tool that highlighted critical information outperformed an unstructured approach regarding transmission of vital information. Nine articles examined telementoring in trauma resuscitation. A common theme was the need to establish an understanding between mentor and provider regarding the limitations of the provider and his or her environment. 

Conclusion: The available data suggest that standardization coupled with short, concise validated scripts could improve efficacy, safety and engagement. Improvements will require multidisciplinary input, practice and deliberate efforts to address barriers.

Finger thoracostomy in patients with chest trauma performed by paramedics on a helicopter emergency medical service

 Liam Hannon, Toby St Clair, Karen Smith, Mark Fitzgerald, Biswadev Mitra, Alexander Olaussen, John Moloney, George Braitberg, Rodney Judson, Warwick Teague, Nuala Quinn, Yesul Kim, Stephen Bernard

 Emerg Med Australas. 2020 Aug;32(4):650-656 

Objective: To determine the frequency of finger thoracostomy performed by intensive care flight paramedics after the introduction of a training programme in this procedure and complications of the procedure that were diagnosed after hospital arrival. 

Methods: This was a retrospective cohort study of adult and paediatric trauma patients undergoing finger thoracostomy performed by paramedics on a helicopter emergency medical service between June 2015 and May 2018. Hospital data were obtained through a manual search of the medical records at each of the three receiving major trauma services. Additional data were sourced from the Victorian State Trauma Registry. 

Results: The final analysis included 103 cases, of which 73.8% underwent bilateral procedures with a total of 179 finger thoracostomies performed. The mean age of patients was 42.8 (standard deviation 21.4) years and 73.8% were male. Motor vehicle collision was the most common mechanism of injury accounting for 54.4% of cases. The median Injury Severity Score was 41 (interquartile range 29-54). There were 30 patients who died pre-hospital, with most (n = 25) having finger thoracostomy performed in the setting of a traumatic cardiac arrest. A supine chest X-ray was performed prior to intercostal catheter insertion in 38 of 73 patients arriving at hospital; of these, none demonstrated a tension pneumothorax. There were three cases of potential complications related to the finger thoracostomy. 

Conclusion: Finger thoracostomy was frequently performed by intensive care flight paramedics. It was associated with a low rate of major complications and given the deficiencies of needle thoracostomy, should be the preferred approach for chest decompression.

Role of the pre-hospital treatment team on the UK military exercise SAIF SAREEA 3 

 Peter Nicholas Harper, N Taylor, P Royal, M B Smith 

BMJ Mil Health 2020 Apr 28;Online ahead of print.

The prehospital treatment team (PHTT) involves a small team working under the clinical supervision of a clinical lead. The clinical lead can be a general duties medical officer (Post Foundation Years Doctor), military nurse practitioner or more senior clinician. The team is mounted in vehicles appropriate to the environment they expect to operate in. A PHTT is closely located to the front line reducing transportation timelines from the point of wounding to more definitive care. The PHTT can provide medical support on the move or when time is available; a more permanent fully erected treatment facility can be established. Either configuration can provide both trauma and primary care. The size of the team allows for multiple trauma subteams enabling care to casualties that arrive simultaneously. The PHTT can move independently which could leave the team vulnerable as there is no integral force protection within the current structure. In such a small team, the right balance of medical and soldiering skills among team members is essential to success. Exercise SAIF SAREEA 3 represented a large-scale battlegroup exercise to the Middle East in the austere desert of Oman. This provided an ideal environment for employing the PHTT concept is a large deployed force undertaking dynamic activity.

An explorative, biomechanical analysis of spine motion during out-of-hospital extrication procedures 

David Häske, Lars Schier, Jeronimo O N Weerts, Berthold Groß, Adrian Rittmann, Paul A Grützner, Matthias Münzberg, Michael Kreinest 

Injury 2020 Feb;51(2):185-192 

Objectives: The extrication of patients following a road traffic collision is among the basic procedures in emergency medicine. Thus, extrication is a frequently performed procedure by most of the emergency medical services worldwide. The appropriate extrication procedure depends on the patient's current condition and accompanying injuries. A rapid extrication should be performed within a few minutes, and the cervical spine (at least) should be immobilized. To our knowledge, the scientific literature and current guidelines do not offer detailed recommendations on the extrication of injured patients. Thus, the aim of the current study is to compare the effectiveness of spinal stabilization during various out-of-hospital extrication procedures. 

Methods: This is an explorative, biomechanical analysis of spine motion during different extrication procedures on an example patient. Movement of the cervical spine was measured using a wireless human motion tracker. Movement of the thoracic and lumbar spine was quantified with 12 strain gauge sensors, which were positioned paravertebrally on both sites along the thoracic and lumbar spine. To interpret angular movement, a motionscore was developed based on newly defined axioms on the biomechanics of the injured spine. 

Results: Self-extrication showed the least spinal movement (overall motionscore sum = 667). Movement in the cervical spine could further be reduced by applying a cervical collar. The extrication by a rescue boa showed comparable results in overall spinal movement compared to the traditional extrication via spineboard (overall motionscore sum = 1862vs. 1743). Especially in the cervical spine, the spinal movement was reduced (motionscore sum = 339 vs. 595). However, the thoracic spine movement was increased (motionscore sum = 812 vs. 432). 

Conclusion: In case of a suspected cervical spine injury, guided self-extrication seems to be the best option. If the patient is not able to perform self-extrication, using a rescue boa might reduce cervical spinal movement compared to the traditional extrication procedure. Since promising results are shown in the case of extrication using a patient transfer sheet that has already been placed below the driver, future developments should focus on novel vehicle seats that already include an extrication device.

A Comparison of Improvised and Commercially Available Point-of-Wounding Tourniquets in Simulated Traumatic Amputation with Catastrophic Hemorrhage

 Aurélie G C Hay-David, Jonathan B T Herron, Andrew Thurgood, Craig Whittle, Ansar Mahmood, Owen Bodger, Timothy J Hodgetts, Ian Pallister

Mil Med 2020 May 19; Online ahead of print. 

Introduction: Catastrophic hemorrhage is the leading cause of preventable trauma deaths in the military and civilian populations. The use of tourniquets by first responders (medical and nonmedically trained) is supported and has the potential to save lives if applied correctly. 

Aims: We sought to examine the use of 5 tourniquets: 1 improvised and 4 commercially available tourniquets to investigate the time taken to stop simulated bleeding and to secure the device; evidence of rebleeding when the "blood pressure" was restored and to gain qualitative feedback on their application. 

Materials and methods: Four commercially available tourniquets (Combat Application Tourniquet [C-A-T], Special Operations Forces Tactical Tourniquet - Wide (SOFTT-W), stretch, wrap, and tuck tourniquet [SWAT-T], and the Tourni-key) and an improvised tourniquet (tie & wooden spoon) were tested on a complex silicone simulation model used to replicate catastrophic hemorrhage from a blast injury with above traumatic knee amputation (SAM 4.1 Trauma Simulation Ltd, UK). To limit the user variability, the same investigator applied each tourniquet and each was tested 3 times. No ethical approval was required to conduct this study. 

Results: None of the devices took longer than 1 minute to secure. The C-A-T and SOFTT-W were quickest to occlude and secure. Although the Tourni-key took longer statistically, this was unlikely to be a clinically important difference. Compared to the others, the SOFTT-W rebled on 2 out of 3 applications. The improvised tourniquet had an obvious ligature effect because of its narrowness, followed by the Tourni-key. This effect was least evident with the SWAT-T; however, particular care was needed to ensure it was safely secured as it was slippery when wet. 

Conclusions: All tourniquets tested were effective and swift to apply. The Tourni-key's antipinch card seems helpful in reducing local pain under the windlass. Reinspection for rebleeding is important and should be routinely performed irrespective of the device. The width of the SWAT-T may be beneficial, thereby, reducing the risk of crush injury.

Face Mask Leak Determines Aerosol Delivery in Noninvasive Ventilation

 Alexandra Haw, Michael McPeck, Ann D Cuccia, Gerald C Smaldone

Respir Care. 2021 Jan;66(1):95-103 

Background: Aerosol transport during noninvasive ventilation follows the flow of pressurized gas through the noninvasive ventilation circuit, vented via leak port and face mask, and inhaled by the patient. Recommendations for nebulizer placement are based on in vitro models that have focused primarily on aerosol losses via the leak port; face mask leaks have been avoided. This study tested aerosol delivery in the setting of controlled face mask leak. 

Methods: Three nebulizer technologies were studied on a bench model using a lung simulator with a face mask placed onto a manikin head. Radiolabeled aerosol delivery (ie, inhaled mass) was determined by mass balance using filters and a gamma camera that tested the effects of nebulizer location and face mask leak. Low (15-20 L/min) and high (55-60 L/min) mask leaks were used to mimic realistic clinical conditions. 

Results: Inhaled mass (% nebulizer charge) was a function of nebulizer technology (with the nebulizer at ventilator outlet position: Aerogen 22.8%, InspiRx 11.1%, and Hudson 8.1%; P = .001). The location of the nebulizer before or after the leak port was not important (P = 0.13 at low leak and P = 0.38 at high leak). Aerosol delivery was minimal with high mask leak (inhaled mass 1.5-7.0%). Aerosol losses at the leak port at low mask leak were 28-36% versus 9-24% at high mask leak. Aerosol losses via the mask leak were 16-20% at low mask leak versus 46-72% at high mask leak. Furthermore, high face mask leak led to significant deposition on the mask and face (eg, up to 50% of the nebulizer charge with the Aerogen mask). 

Conclusions: During noninvasive ventilation, nebulizer placement at the ventilator outlet, which is a more practical position, is effective and minimizes deposition on face and mask. Aerosol therapy should be avoided when there is high face mask leak.

A Comparison of Improvised and Commercially Available Point-of-Wounding Tourniquets in Simulated Traumatic Amputation with Catastrophic Hemorrhage

 Aurélie G C Hay-David, Jonathan B T Herron, Andrew Thurgood, Craig Whittle, Ansar Mahmood, Owen Bodger, Timothy J Hodgetts, Ian Pallister 

Mil Med. 2020 Sep 18;185(9-10):e1536-e1541 

Introduction: Catastrophic hemorrhage is the leading cause of preventable trauma deaths in the military and civilian populations. The use of tourniquets by first responders (medical and nonmedically trained) is supported and has the potential to save lives if applied correctly. 

Aims: We sought to examine the use of 5 tourniquets: 1 improvised and 4 commercially available tourniquets to investigate the time taken to stop simulated bleeding and to secure the device; evidence of rebleeding when the "blood pressure" was restored and to gain qualitative feedback on their application. 

Materials and methods: Four commercially available tourniquets (Combat Application Tourniquet [C-A-T], Special Operations Forces Tactical Tourniquet - Wide (SOFTT-W), stretch, wrap, and tuck tourniquet [SWAT-T], and the Tourni-key) and an improvised tourniquet (tie & wooden spoon) were tested on a complex silicone simulation model used to replicate catastrophic hemorrhage from a blast injury with above traumatic knee amputation (SAM 4.1 Trauma Simulation Ltd, UK). To limit the user variability, the same investigator applied each tourniquet and each was tested 3 times. No ethical approval was required to conduct this study. 

Results: None of the devices took longer than 1 minute to secure. The C-A-T and SOFTT-W were quickest to occlude and secure. Although the Tourni-key took longer statistically, this was unlikely to be a clinically important difference. Compared to the others, the SOFTT-W rebled on 2 out of 3 applications. The improvised tourniquet had an obvious ligature effect because of its narrowness, followed by the Tourni-key. This effect was least evident with the SWAT-T; however, particular care was needed to ensure it was safely secured as it was slippery when wet. 

Conclusions: All tourniquets tested were effective and swift to apply. The Tourni-key's antipinch card seems helpful in reducing local pain under the windlass. Reinspection for rebleeding is important and should be routinely performed irrespective of the device. The width of the SWAT-T may be beneficial, thereby, reducing the risk of crush injury.

Authors' Reply to the Response to Our Article ("A Comparison of Improvised and Commercially Available Point-of-Wounding Tourniquets in Simulated Traumatic Amputation with Catastrophic Haemorrhage")

 Aurélie G C Hay-David, Jonathan B T Herron, Andrew Thurgood, Craig Whittle, Ansar Mahmood, Owen Bodger, Timothy J Hodgetts, Ian Pallister 

Mil Med. 2020 Oct 10;usaa264. doi: 10.1093/milmed/usaa264. Online ahead of print. 

No abstract available

Tranexamic acid for acute traumatic hemorrhage in emergency medicine: why not, but…

Matthieu Heidet

Eur J Emerg Med 2020 Apr;27(2):85-86 

Current guidelines broadly recommend using TXA in severely injured patients. While TXA appears to be cheap, easy, well tolerated and efficient, clinicians should remain aware of the limitations of the available results, remind that TXA should be used within precise indications, in accordance with broader key practices in trauma patients, and look forward to answering pending interrogations. Clinicians should adopt a cautious approach in order to limit their use of TXA to the most severe patients and stay aware that many gaps remain unanswered to date. 

Current strategy of ‘rapid TXA for all’ may improperly lead to overexpose patients who would not benefit from this practice.

Reliability of prehospital patient classification in helicopter emergency medical service missions

 A Heino, P Laukkanen-Nevala, L Raatiniemi, M Tommila, J Nurmi, A Olkinuora, I Virkkunen, T Iirola 

BMC Emerg Med 2020 May 25;20(1):42 

Background: Several scores and codes are used in prehospital clinical quality registries but little is known of their reliability. The aim of this study is to evaluate the inter-rater reliability of the American Society of Anesthesiologists physical status (ASA-PS) classification system, HEMS benefit score (HBS), International Classification of Primary Care, second edition (ICPC- 2) and Eastern Cooperative Oncology Group (ECOG) performance status in a helicopter emergency medical service (HEMS) clinical quality registry (CQR). 

Methods: All physicians and paramedics working in HEMS in Finland and responsible for patient registration were asked to participate in this study. The participants entered data of six written fictional missions in the national CQR. The inter-rater reliability of the ASA-PS, HBS, ICPC-2 and ECOG were evaluated using an overall agreement and free-marginal multi-rater kappa (Κfree). 

Results: All 59 Finnish HEMS physicians and paramedics were invited to participate in this study, of which 43 responded and 16 did not answer. One participant was excluded due to unfinished data entering. ASA-PS had an overall agreement of 40.2% and Κfree of 0.28 in this study. HBS had an overall agreement of 44.7% and Κfree of 0.39. ICPC-2 coding had an overall agreement of 51.5% and Κfree of 0.47. ECOG had an overall agreement of 49.6% and Κfree of 0.40. 

Conclusion: This study suggests a marked inter-rater unreliability in prehospital patient scoring and coding even in a relatively uniform group of practitioners working in a highly focused environment. This indicates that the scores and codes should be specifically designed or adapted for prehospital use, and the users should be provided with clear and thorough instructions on how to use them.

Partial Versus Complete Resuscitative Endovascular Balloon Occlusion of the Aorta in Exsanguinating Trauma Patients With Non-Compressible Torso Hemorrhage

 Stacey E Heindl, Dwayne A Wiltshire, Ilmaben S Vahora, Nicholas Tsouklidis, Safeera Khan 

Cureus. 2020 Jul 4;12(7):e8999. doi: 10.7759/cureus.8999 

Abstract 

Hemorrhage is a major cause of death globally, yet our options to control the condition have remained limited. The standard intervention for patients suffering from a non-compressible torso hemorrhage (NCTH) typically involves resuscitative thoracotomy (RT) with aortic cross-clamping. Apart from being extraordinarily invasive, the survival rates for this procedure remain low. Over the years, research has surfaced that offers much promise regarding the use of resuscitative endovascular balloon occlusion of the aorta (REBOA) in exsanguinating patients. Although this type of procedure is not yet universally recognized as a gold standard, it holds some hope for the development of additional research regarding how we can make use of this advancement to improve survival in trauma patients. Complete REBOA (c-REBOA) has not gained wide acceptance due to the undeniable effects it has on normal physiology, metabolic effects, long-term complications, and mortality. Partial REBOA (p-REBOA) is not yet fully validated by research but could potentially be the answer to our problem. The critical question that we should address at this juncture is as follows: how can we improve the survival of patients with an NCTH in the least invasive way possible, while also reducing the feared complications associated with c-REBOA?

Who Would Have Benefited from the Prehospital Use of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA)? An Autopsy Study (Need Link)

Reynold Henry, Kazuhide Matsushima, Rachel N Henry, Victor Wong, Zachary Warriner, Aaron Strumwasser, Christopher P Foran, Kenji Inaba, Todd E Rasmussen, Demetrios Demetriades 

J Am Coll Surg 2019 Oct;229(4):383-388  

Background: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been increasingly used as part of damage control resuscitation for patients with non-compressible truncal hemorrhage. We hypothesized that there might be a select group of patients that could have benefited from prehospital placement of the REBOA.

Study design: This was a retrospective cohort study including patients who presented to a Level I trauma center with cardiac arrest between January 2014 and March 2018. The findings of a full autopsy were reviewed for the details of internal injuries. A patient was determined to be a REBOA candidate if the patient sustained abdominal organ injuries or pelvic fractures and no associated severe head injuries. The candidate group was compared with the non-candidate group based on prehospital vital signs and other patient characteristics. A multiple logistic regression analysis was performed to identify certain prehospital factors associated with candidacy for prehospital REBOA.

Results: A total of 198 patients met our inclusion criteria. Of those, 27 (13.6%) patients were deemed REBOA candidates. Median Injury Severity Score was 22 (interquartile range 17 to 29). Patients in the candidate group were more likely to have a Glasgow Coma Scale score ≥9 (48% vs 15%; p = 0.012), oxygen saturation >90% (56% vs 35%; p = 0.03), and systolic blood pressure <90 mmHg (48% vs 26%; p = 0.04) in the field. Logistic regression showed that these 3 clinical parameters of prehospital vital signs were significantly associated with REBOA candidacy.

Conclusions: Our data suggest that >10% of trauma patients who presented with cardiac arrest could have benefited from prehospital REBOA. Additional prospective studies are warranted to validate the use of field vital signs in selecting candidates.

Is prehospital endobronchial intubation a risk factor for subsequent ventilator associated pneumonia? A retrospective analysis

Ana Catalina Hernandez Padilla, Timothée Trampont, Thomas Lafon, Thomas Daix, Dominique Cailloce, Olivier Barraud, François Dalmay, Philippe Vignon, Bruno François

PLoS One 2019 May 23;14(5):e0217466 

Abstract

More than half of patients under mechanical ventilation in the intensive care unit (ICU) are field- intubated, which is a known risk factor for ventilator associated pneumonia (VAP). We assessed whether field endobronchial intubation (EBI) is associated with the development of subsequent VAP during the ICU stay. This retrospective, nested case-control study was conducted in a cohort of field-intubated patients admitted to an ICU of a teaching hospital during a three-year period. Cases were defined as field-intubated patients with EBI and controls corresponded to field-intubated patients with proper position of the tracheal tube on admission chest X-ray.

Primary endpoint was the development of early VAP. Secondary endpoints included the development of early ventilator associated tracheo-bronchitis, late VAP, duration of mechanical ventilation, length of stay and mortality in the ICU. A total of 145 patients were studied (mean age: 54 ± 19 years; men: 74%). Reasons for field intubation were predominantly multiple trauma (49%) and cardiorespiratory arrest (38%). EBI was identified in 33 patients (23%). Fifty-three patients (37%) developed early or late VAP. EBI after field intubation was associated with a nearly two-fold increase of early VAP, though not statistically significant (30% vs. 17%: p = 0.09). No statistically significant difference was found regarding secondary outcomes. The present study suggests that inadvertent prehospital EBI could be associated with a higher incidence of early-onset VAP. Larger studies are required to confirm this hypothesis. Whether strategies aimed at decreasing the incidence and duration of EBI could reduce the incidence of subsequent VAP remains to be determined.

Novel CASEVAC method in austere conditions

Jonathan Blair Thomas Herron, P Alleway 

BMJ Mil Health. 2020 Oct;166(5):360-361 

No abstract available

 

Re-introducing whole blood for transfusion: considerations for blood providers

 Tor A Hervig, Heidi A Doughty, Rebecca A Cardigan, Torunn O Apelseth, John R Hess, Femke Noorman, Miloš Bohoněk, Mark H Yazer, Jia Lu, Silvano Wendel, Rosemary L Sparrow, Biomedical Excellence for Safer Transfusion Collaborative 

Vox Sang. 2021 Feb;116(2):167-174 

Abstract

Whole blood is the original blood preparation but disappeared from the blood bank inventories in the 1980s following the advent of component therapy. In the early 2000s, both military and civilian practice called for changes in the transfusion support for massive haemorrhage. The 'clear fluid' policy was abandoned and replaced by early balanced transfusion of platelets, plasma and red cells. Whole blood is an attractive alternative to multi-component therapy, which offers reduced hemodilution, lower donor exposure and simplified logistics. However, the potential for wider re-introduction of whole blood requires re-evaluation of haemolysins, storage conditions and shelf-life, the need for leucocyte depletion/ pathogen reduction and inventory management for blood providers. This review addresses these questions and calls for research to define the optimal whole blood product and the indications for its use.

Pre-hospital CPR and early REBOA in trauma patients - results from the ABOTrauma Registry

Peter Hilbert-Carius, David T McGreevy, Fikri M Abu-Zidan, Tal M Hörer, the ABOTrauma Registry research group

World J Emerg Surg 2020 Mar 30;15(1):23

Background: Severely injured trauma patients suffering from traumatic cardiac arrest (TCA) and requiring cardiopulmonary resuscitation (CPR) rarely survive. The role of resuscitative endovascular balloon occlusion of the aorta (REBOA) performed early after hospital admission in patients with TCA is not well-defined. As the use of REBOA increases, there is great interest in knowing if there is a survival benefit related to the early use of REBOA after TCA. Using data from the ABOTrauma Registry, we aimed to study the role of REBOA used early after hospital admission in trauma patients who required pre-hospital CPR.

Methods: Retrospective and prospective data on the use of REBOA were collected from the ABOTrauma Registry from 11 centers in seven countries globally between 2014 and 2019. In all patients with pre-hospital TCA, the predicted probability of survival, calculated with the Revised Injury Severity Classification II (RISC II), was compared with the observed survival rate.

Results: Of 213 patients in the ABOTrauma Registry, 26 patients (12.2%) who had received pre-hospital CPR were identified. The median (range) Injury Severity Score (ISS) was 45.5 (25- 75). Fourteen patients (54%) had been admitted to the hospital with ongoing CPR. Nine patients (35%) died within the first 24 h, while seventeen patients (65%) survived post 24 h. The survival rate to hospital discharge was 27% (n = 7). The predicted mortality using the RISC II was 0.977 (25 out of 26). The observed mortality (19 out of 26) was significantly lower than the predicted mortality (p = 0.049). Patients not responding to REBOA were more likely to die. Only one (10%) out of 10 non-responders survived. The survival rate in the 16 patients responding to REBOA was 37.5% (n = 6). REBOA with a median (range) duration of 45 (8-70) minutes significantly increases blood pressure from the median (range) 56.5 (0-147) to 90 (0-200) mmHg.

Conclusions: Mortality in patients suffering from TCA and receiving REBOA early after hospital admission is significantly lower than predicted by the RISC II. REBOA may improve survival after TCA. The use of REBOA in these patients should be further investigated.

Mechanical ventilation of patients in helicopter emergency medical service transport: an international survey

Peter Hilbert-Carius, Manuel F Struck, Veronika Hofer, Jochen Hinkelbein, Leif Rognås, Jörn Adler, Michael D Christian, Thomas Wurmb, Michael Bernhard, Björn Hossfeld

Scand J Trauma Resusc Emerg Med. 2020 Nov 18;28(1):112

Background: Mechanical ventilation in helicopter emergency medical service (HEMS) environments is a procedure which carries a significant risk of complications. Limited data on the quality and performance of mechanical ventilation in HEMS are available in the literature.

Method: We conducted an international survey to evaluate mechanical ventilation infrastructure in HEMS and collect data of transported ventilated patients. From June 20-22, 2019, the participating HEMS bases were asked to provide data via a web-based platform. Vital parameters and ventilation settings of the patients at first patient contact and at handover were compared using non-parametric statistical tests.

Results: Out of 215 invited HEMS bases, 53 responded. Respondents were from Germany, Denmark, United Kingdom, Luxembourg, Austria and Switzerland. Of the HEMS bases, all teams were physician staffed, mainly anesthesiologists (79%), the majority were board certified (92.5%) and trained in intensive care medicine (89%) and had a median (range) experience in HEMS of 9 (0-25) years. HEMS may provide a high level of expertise in mechanical ventilation whereas the majority of ventilators are able to provide pressure controlled ventilation and continuous positive airway pressure modes (77%). Data of 30 ventilated patients with a median (range) age of 54 (21-100) years and 53% male gender were analyzed. Of these, 24 were primary missions and 6 interfacility transports. At handover, oxygen saturation (p < 0.01) and positive end-expiratory pressure (p = 0.04) of the patients were significantly higher compared to first patient contact.

Conclusion: In this survey, the management of ventilated HEMS-patients was not associated with ventilation related serious adverse events. Patient conditions, training of medical crew and different technical and environmental resources are likely to influence management. Further studies are necessary to assess safety and process quality of mechanical ventilation in HEMS.

OMNA Marine Tourniquet Self-Application

Emma Hingtgen, Piper L Wall, Charisse M Buising

J Spec Oper Med. Fall 2020;20(3):52-61

 Background: The OMNA Marine Tourniquet is a 5.1cm-wide, simple redirect buckle, hoop-and-loop secured, ratcheting tourniquet designed for storage and use in marine environments. This study evaluated self-application effectiveness and pressures.

Methods: Triplicate secured, occlusion, and completion pressures were measured during 60 subjects pulling down or up thigh applications and nondominant, single-handed arm applications. Arm pressure measurements required circumferences =30cm.

Results: Thirty-one subjects had arm circumferences ≥30cm. All 540 applications were effective; 376 of 453 applications had known secured pressures >150mmHg (89 of 93 arm). Thigh down versus up pulling directions were not different (secured, occlusion, and completion pressures and ladder tooth advances). Occlusion pressures were 348mmHg (275-521mmHg) for combined thighs and 285mmHg (211-372mmHg) for arms. Completion pressures were 414mmHg (320-588mmHg) for combined thighs and 344mmHg (261-404mmHg) for arms. Correlations between secured pressures and occlusion ladder tooth advances (clicks) were r2 = 0.44 for combined thighs and 0.68 for arms. Correlations between occlusion pressures and occlusion clicks were poor (r2 = 0.24, P < .0001 for combined thighs and r2 = 0.027, P = .38 for arms).

Conclusions: The OMNA Marine Tourniquet can be self-applied effectively, including one-handed applications. Occlusion and completion pressures are similar to reported 3.8cm-wide Ratcheting Medical Tourniquet pressures.

Cardiopulmonary resuscitation (CPR) during spaceflight - a guideline for CPR in microgravity from the German Society of Aerospace Medicine (DGLRM) and the European Society of Aerospace Medicine Space Medicine Group (ESAM-SMG)

Jochen Hinkelbein, Steffen Kerkhoff, Christoph Adler, Anton Ahlbäck, Stefan Braunecker, Daniel Burgard, Fabrizio Cirillo, Edoardo De Robertis, Eckard Glaser, Theresa K Haidl, Pete Hodkinson, Ivan Zefiro Iovino, Stefanie Jansen, Kolaparambil Varghese Lydia Johnson, Saskia Jünger, Matthieu Komorowski, Marion Leary, Christina Mackaill, Alexander Nagrebetsky, Christopher Neuhaus, Lucas Rehnberg, Giovanni Marco Romano, Thais Russomano, Jan Schmitz, Oliver Spelten, Clément Starck, Seamus Thierry, Rochelle Velho, Tobias Warnecke

Scand J Trauma Resusc Emerg Med. 2020 Nov 2;28(1):108

 Background: With the "Artemis"-mission mankind will return to the Moon by 2024. Prolonged periods in space will not only present physical and psychological challenges to the astronauts, but also pose risks concerning the medical treatment capabilities of the crew. So far, no guideline exists for the treatment of severe medical emergencies in microgravity. We, as a international group of researchers related to the field of aerospace medicine and critical care, took on the challenge and developed a an evidence-based guideline for the arguably most severe medical emergency - cardiac arrest.

Methods: After the creation of said international group, PICO questions regarding the topic cardiopulmonary resuscitation in microgravity were developed to guide the systematic literature research. Afterwards a precise search strategy was compiled which was then applied to "MEDLINE". Four thousand one hundred sixty-five findings were retrieved and consecutively screened by at least 2 reviewers. This led to 88 original publications that were acquired in full-text version and then critically appraised using the GRADE methodology. Those studies formed to basis for the guideline recommendations that were designed by at least 2 experts on the given field. Afterwards those recommendations were subject to a consensus finding process according to the DELPHI-methodology.

Results: We recommend a differentiated approach to CPR in microgravity with a division into basic life support (BLS) and advanced life support (ALS) similar to the Earth-based guidelines. In immediate BLS, the chest compression method of choice is the Evetts-Russomano method (ER), whereas in an ALS scenario, with the patient being restrained on the Crew Medical Restraint System, the handstand method (HS) should be applied. Airway management should only be performed if at least two rescuers are present and the patient has been restrained. A supraglottic airway device should be used for airway management where crew members untrained in tracheal intubation (TI) are involved.

Discussion: CPR in microgravity is feasible and should be applied according to the Earth-based guidelines of the AHA/ERC in relation to fundamental statements, like urgent recognition and action, focus on high-quality chest compressions, compression depth and compression-ventilation ratio. However, the special circumstances presented by microgravity and spaceflight must be considered concerning central points such as rescuer position and methods for the performance of chest compressions, airway management and defibrillation.

French military deaths in Afghanistan: a retrospective analysis of 450 combat casualties between 2010 and 2012

Clément Hoffmann, C Poyat, L Alhanati, R Haus-Cheymol, S de Rudnicki, J Bouix-Picasso, N Donat

BMJ Mil Health. 2021 Apr;167(2):140

 No abstract available

Development of a New Vented Chest Seal Dressing for Treatment of Open Pneumothorax

Andrew Hoggarth, Matthew Grist, Bryony Board, Toni Murch

J Spec Oper Med. Fall 2020;20(3):159-165 

Abstract

The most common life-threatening complications from both blunt and penetrating thoracic injury are hemothorax, pneumothorax, or a combination of both. New guidelines, set out by the Tactical Combat Casualty Care (TCCC), advises that vented chest seal dressings are used to manage open or sucking chest wounds. Designing out risk is a fundamental criterion for ensuring the optimal performance of a device is obtained that offers the casualty the greatest chance of survival. Two key areas of risk in the application of vented chest seal dressings are adhesion failure and vent failure. This study assesses a new design of vented chest seal dressing for both adhesion and vent profile. The development of this new design for a vented chest seal has been tested for adhesion and venting properties and shown to have performance criteria suitable for the treatment of open pneumothorax and design features that minimize the risk of product failure during use.

Ketamine vs. haloperidol for prevention of cognitive dysfunction and postoperative delirium: A phase IV multicentre randomised placebo-controlled double-blind clinical trial

Alexa Hollinger, Christoph A Rüst, Harriet Riegger, Bianca Gysi, Fabian Tran, Jonas Brügger, Jan Huber, Katharina Toft, Madlen Surbeck, Hans-Ruedi Schmid, Katharina Rentsch, Luzius Steiner, Martin Siegemund

J Clin Anesth. 2021 Feb;68:110099. doi: 10.1016/j.jclinane.2020.110099. Epub 2020 Oct 22

 Study objective: Delirium is frequently observed in the postoperative and intensive care unit (ICU) population. Due to the multifactorial origin of delirium and according to international guidelines (e.g., American Geriatrics Society; Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption (PADIS) guideline), there are several but no incontestable options for prevention and symptomatic treatment. The purpose of the Baden PRIDe (Prevention and Reduction of Incidence of postoperative Delirium) trial was to determine whether postoperative cognitive dysfunction and delirium could be prevented by the combination of possible preventive agents such as haloperidol and ketamine. In addition, pre- and postoperative levels of the biomarkers cortisol, neuron specific enolase (NSE) and S100β were measured to investigate their dynamics in delirious and non-delirious patients after surgery.

Design: The Baden PRIDe Trial was an investigator-initiated, phase IV, two-centre, randomised, placebo-controlled, double-blind clinical trial.

Setting: Perioperative care.

Patients: 182 adult patients that underwent elective or emergency surgery under general or combined (i.e., general and regional) anaesthesia.

Interventions: Pre-anaesthetic, pharmacologic prevention of postoperative brain dysfunction with haloperidol, ketamine, and the combination of both vs. placebo.

Measurements: Assessment of cognitive performance pre- and postoperatively with the MMSE, the DOS, the Nursing Delirium Screening Scale (Nu-DESC) or the Intensive Care Delirium Screening Checklist (ICDSC) during ICU stay.

Main results: None of the three study arms - haloperidol, ketamine, or both drugs combined - was significantly superior to placebo for prevention of postoperative brain dysfunction and delirium (P = 0.39). Measured levels of postoperative cortisol were significantly higher in delirious patients. S-100β levels were significantly higher in all postoperative outcome groups (cognitive impairment, delirium, no cognitive decline), whereas postoperative NSE levels declined in all groups.

Conclusions: The study results offer no possibility for a novel recommendation for prevention of postoperative cognitive decline including delirium. Perioperative S-100β trajectories in patients with cognitive deterioration suggest affection of glial cells in particular.

First pass success of tracheal intubation using the C-MAC PM videolaryngoscope as first-line device in prehospital cardiac arrest compared with other emergencies: An observational study

Bjoern Hossfeld, Sylvi Thierbach, Andreas Allgoewer, Holger Gaessler, Matthias Helm

Eur J Anaesthesiol. 2020 Aug 21. doi: 10.1097/EJA.0000000000001286. Online ahead of print.

 Background: Successful airway management is a priority in the resuscitation of critically ill or traumatised patients. Several studies have demonstrated the importance of achieving maximum first pass success, particularly in prehospital advanced airway management.

Objective: To compare success rates of emergency intubations between patients requiring cardiopulmonary resuscitation (CPR) for cardiac arrest (CPR group) and other emergencies (non-CPR group) using the C-MAC PM videolaryngoscope.

Design: Ongoing analysis of prospective collected prehospital advanced airway management core variables.

Setting: Single helicopter emergency medical service (HEMS) 'Christoph 22', Ulm Military Hospital, Germany, May 2009 to July 2018.

Patients: We included all 1006 HEMS patients on whom prehospital advanced airway management was performed by board-certified anaesthesiologists on call at HEMS 'Christoph 22'.

Interventions: The C-MAC PM was used as the first-line device. The initial direct laryngoscopy was carried out using the C-MAC PM without the monitor in sight. After scoring the direct laryngoscopic view according to the Cormack and Lehane grade, the monitor was folded within the sight of the physician and tracheal intubation was performed using the videolaryngoscopic view without removing the blade.

Main outcome measures: The primary outcome was successful airway management. Secondary outcomes were the patient's position during airway management, necessity for suction, direct and videolaryngoscopic view according to Cormack and Lehane grading, as well as number of attempts needed for successful intubation.

Results: A patent airway was achieved in all patients including rescue techniques. There was a lower first pass success rate in the CPR group compared with the non-CPR group (84.4 vs. 91.4%, P = 0.01). In the CPR group, direct laryngoscopy resulted more often in a clinically unfavourable (Cormack and Lehane grade 3 or 4) glottic view (CPR vs. non-CPR-group 37.2 vs. 26.7%, P = 0.0071). Using videolaryngoscopy reduced the clinically unfavourable grading to Cormack and Lehane 1 or 2 (P < 0.0001). The odds of achieving first pass success were approximately 12-fold higher with a favourable glottic view than with an unfavourable glottic view (OR 12.6, CI, 6.70 to 23.65).

Conclusion: Airway management in an anaesthesiologist-staffed HEMS is associated with a high first pass success rate but even with skilled providers using the C-MAC PM videolaryngoscope routinely, patients who require CPR offer more difficulties for successful prehospital advanced airway management at the first attempt.

Risk Values of Weight and Body Mass Index for Chest Wall Thickness in Patients Requiring Needle Thoracostomy Decompression

Chia-Hung Hsu, Tzu-Yin Lin, Ju-Chi Ou, Jiann Ruey Ong, Hon-Ping Ma

Emerg Med Int. 2020 Oct 26;2020:2070157. doi: 10.1155/2020/2070157

 Abstract

Introduction: Emergency decompression is needed in patients with tension pneumothorax, a life-threatening condition. The catheter-based needle thoracostomy was suggested using a 5 cm catheter inserted into the 2nd intercostal space (ICS) and 5th ICS according to the ninth and tenth editions of Advanced Trauma Life Support, respectively. A catheter of suitable length may not be available immediately or the muscle structure of the chest wall may be modified in pneumothorax. Furthermore, alternative sites for needle thoracostomy and reference values of chest wall thickness (CWT) should be explored and warranted.

Method: CT scan data and medical data of 650 eligible patients from October 2016 to December 2016 were reviewed. CWT values at four ICSs as well as four variables, namely, age, weight, height, and body mass index (BMI) for both men and women were compared using a nonparametric method, namely, the Wilcoxon signed-rank test. The associations between CWT and the four variables were assessed using the Pearson correlation coefficient. The overall performance of BMI, weight, and height in predicting CWT > 5 cm was evaluated using the receiver-operating characteristic (ROC) curve. Finally, the prediction models were built by using the bootstrap method.

Results: Four variables, namely, age, height, weight, and BMI, were compared between the men and women groups. All four variables differed significantly between the two groups, and CWTs at all ICSs, except for the 3rd ICS, differed significantly between the two groups. Among the women, the area under the ROC curve (AUROC) of BMI for predicting CWT > 5 cm at 2nd ICS was larger than the AUROC of weight and height. Among the men, the AUROC of weight for predicting CWT > 5 cm at 2nd ICS was larger than that of BMI and height. The reference value tables were provided for five proposed models for women and men, respectively. Under emergencies, the variable, BMI, or even weight itself, could be used for predicting a failure performance of the needle decompression. For women, CWT at 5th ICS was predicted over 5 cm at BMI over 25.9 kg/m2 or weight over 103.1 kg. For men, CWT at 5th ICS was predicted over 5 cm at BMI over 25.5 kg/m2 or weight over 157.4 kg.

Conclusion: Needle thoracostomy is the preferred first technique for many emergency providers for decompression. Therefore, a reference table for safe needle thoracostomy decompression at four usual sites, namely, 2nd ICS, 3rd CIS, 4th ICS, and 5th ICS, was recommended, which will enable paramedics and emergency specialists to rapidly determine CWT at the appropriate ICSs during emergencies.

Sufentanil attenuates inflammation and oxidative stress in sepsis-induced acute lung injury by downregulating KNG1 expression

Quan Hu, Qin Wang, Chuangang Han, Yan Yang

Mol Med Rep. 2020 Nov;22(5):4298-4306 

Abstract

The present study aimed to investigate the effects of sufentanil on sepsis-induced acute lung injury (ALI), and identify the potential molecular mechanisms underlying its effect. In order to achieve this, a rat sepsis model was established. Following treatment with sufentanil, the lung wet/dry (W/D) weight ratio was calculated. Histopathological analysis was performed via hematoxylin and eosin staining. Levels of inflammatory factors in bronchoalveolar lavage fluid were determined via ELISA. Furthermore, malondialdehyde (MDA) content and the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in tissue homogenates were assessed using commercial kits. Western blot analysis was performed to determine kininogen-1 (KNG1) protein expression. In addition, alveolar epithelial type II cells (AEC II) were stimulated with lipopolysaccharide (LPS) to mimic ALI. The levels of inflammation and oxidative stress were evaluated following overexpression of KNG1. Protein expression levels of nuclear factor-κB (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling were determined via western blot analysis. The results of the present study demonstrated that sufentanil alleviated histopathological injury and the W/D ratio in lung tissue. Following treatment with sufentanil, levels of inflammatory factors also decreased, accompanied by decreased concentrations of MDA, and increased activities of SOD, CAT and GSH-Px. Notably, KNG1 was decreased in lung tissues following treatment with sufentanil. Furthermore, overexpression of KNG1 attenuated the inhibitory effects of sufentanil on LPS-induced inflammation and oxidative stress in AEC II. Sufentanil markedly downregulated NF-κB expression, while upregulating Nrf2 and HO-1 expression levels, which was reversed following overexpression of KNG1. Taken together, the results of the present study suggested that sufentanil may alleviate inflammation and oxidative stress in sepsis-induced ALI by downregulating KNG1 expression.

Low-dose ketamine affects blood pressure, but not muscle sympathetic nerve activity, during progressive central hypovolemia without altering tolerance

Mu Huang, Joseph C Watso, Gilbert Moralez, Matthew N Cramer, Joseph M Hendrix, Jeung-Ki Yoo, Mark B Badrov, Qi Fu, Carmen Hinojosa-Laborde, Craig G Crandall

J Physiol. 2020 Dec;598(24):5661-5672

Key points: Haemorrhage is the leading cause of battlefield and civilian trauma deaths. Given that a haemorrhagic injury on the battlefield is almost always associated with pain, it is paramount that the administered pain medication does not disrupt the physiological mechanisms that are beneficial in defending against the haemorrhagic insult. Current guidelines from the US Army's Committee on Tactical Combat Casualty Care (CoTCCC) for the selection of pain medications administered to a haemorrhaging soldier are based upon limited scientific evidence, with the clear majority of supporting studies being conducted on anaesthetized animals. Specifically, the influence of low-dose ketamine, one of three analgesics employed in the pre-hospital setting by the US Army, on haemorrhagic tolerance in humans is unknown. For the first time in conscious males and females, the findings of the present study demonstrate that the administration of an analgesic dose of ketamine does not compromise tolerance to a simulated haemorrhagic insult. Increases in muscle sympathetic nerve activity during progressive lower-body negative pressure were not different between trials. Despite the lack of differences for muscle sympathetic nerve activity responses, mean blood pressure and heart rate were higher during moderate hypovolemia after ketamine vs. placebo administration.

Abstract: Haemorrhage is the leading cause of battlefield and civilian trauma deaths. For a haemorrhaging soldier, there are several pain medications (e.g. ketamine) recommended for use in the prehospital, field setting. However, the data to support these recommendations are primarily limited to studies in animals. Therefore, it is unknown whether ketamine adversely affects physiological mechanisms responsible for maintenance of arterial blood pressure (BP) during haemorrhage in humans. In humans, ketamine has been demonstrated to raise resting BP, although it has not been studied with the concomitant central hypovolemia that occurs during haemorrhage. Thus, the present study aimed to test the hypothesis that ketamine does not impair haemorrhagic tolerance in humans. Thirty volunteers (15 females) participated in this double-blinded, randomized, placebo-controlled trial. A pre-syncopal limited progressive lower-body negative pressure (LBNP; a validated model for simulating haemorrhage) test was conducted following the administration of ketamine (20 mg) or placebo (saline). Tolerance was quantified as a cumulative stress index and compared between trials using a paired, two-tailed t test. We compared muscle sympathetic nerve activity (MSNA; microneurography), beat-to-beat BP (photoplethysmography) and heart rate (electrocardiogram) responses during the LBNP test using a mixed effects model (time [LBNP stage] × drug). Tolerance to the LBNP test was not different between trials (Ketamine: 635 ± 391 vs. Placebo: 652 ± 360 mmHg‧min, p = 0.77). Increases in MSNA burst frequency (time: P < 0.01, trial: p = 0.27, interaction: p = 0.39) during LBNP stages were no different between trials. Despite the lack of differences for MSNA responses, mean BP (time: P < 0.01, trial: P < 0.01, interaction: p = 0.01) and heart rate (time: P < 0.01, trial: P < 0.01, interaction: P < 0.01) were higher during moderate hypovolemia after ketamine vs. placebo administration (P < 0.05 for all, post hoc), but not at the end of LBNP. These data, which are the first to be obtained in conscious humans, demonstrate that the administration of low-dose ketamine does not impair tolerance to simulated haemorrhage or mechanisms responsible for maintenance of BP.

Analysis of Casualties That Underwent Airway Management Before Reaching Role 2 Facilities in the Afghanistan Conflict 2008-2014

Ian L Hudson, Megan B Blackburn, Amanda M Staudt, Kathy L Ryan, Elizabeth A Mann- Salinas

Mil Med 2020 Jan 7;185(Suppl 1):10-18

 Abstract

Introduction: Airway compromise is the second leading cause of potentially survivable death on the battlefield. The purpose of this study was to better understand wartime prehospital airway patients.

Materials and methods: The Role 2 Database (R2D) was retrospectively reviewed for adult patients injured in Afghanistan between February 2008 and September 2014. Of primary interest were prehospital airway interventions and mortality. Prehospital combat mortality index (CMI-PH), hemodynamic interventions, injury mechanism, and demographic data were also included in various statistical analyses.

Results: A total of 12,780 trauma patients were recorded in the R2D of whom 890 (7.0%) received prehospital airway intervention. Airway intervention was more common in patients who ultimately died (25.3% vs. 5.6%); however, no statistical association was found in a multivariable logistic regression model (OR 1.28, 95% CI 0.98-1.68). Compared with U.S. military personnel, other military patients were more likely to receive airway intervention after adjusting for CMI-PH (OR 1.33, 95% CI 1.07-1.64).

Conclusions: In the R2D, airway intervention was associated with increased odds of mortality, although this was not statistically significant. Other patients had higher odds of undergoing an airway intervention than U.S. military. Awareness of these findings will facilitate training and equipment for future management of prehospital/prolonged field care airway interventions.

 

Recommendations for burns care in mass casualty incidents: WHO Emergency Medical Teams Technical Working Group on Burns (WHO TWGB) 2017-2020

 Amy Hughes, Stian Kreken Almeland, Thomas Leclerc, Takayuki Ogura, Minoru Hayashi, Jody-Ann Mills, Ian Norton, Tom Potokar

Burns. 2021 Mar;47(2):349-370

 Abstract 

Health and logistical needs in emergencies have been well recognised. The last 7 years has witnessed improved professionalisation and standardisation of care for disaster affected communities - led in part by the World Health Organisation Emergency Medical Team (EMT) initiative. Mass casualty incidents (MCIs) resulting in burn injuries present unique challenges. Burn management benefits from specialist skills, expert knowledge, and timely availability of specialist resources. With burn MCIs occurring globally, and wide variance in existing burn care capacity, the need to strengthen burn care capability is evident. Although some high-income countries have well-established disaster management plans, including burn specific plans, many do not - the majority of countries where burn mass casualty events occur are without such established plans. Developing globally relevant recommendations is a first step in addressing this deficit and increasing preparedness to deal with such disasters. Global burn experts were invited to a succession of Technical Working Group on burns (TWGB) meetings to: 1) review literature on burn care in MCIs; and 2) define and agree on recommendations for burn care in MCIs. The resulting 22 recommendations provide a framework to guide national and international specialist burn teams and health facilities to support delivery of safe care and improved outcomes to burn patients in MCIs.

Enhanced prehospital volume therapy does not lead to improved outcomes in severely injured patients with severe traumatic brain injury

 Bjoern Hussmann, Carsten Schoeneberg, Pascal Jungbluth, Matthias Heuer, Rolf Lefering, Teresa Maek, Frank Hildebrand, Sven Lendemans, Hans-Christoph Pape

BMC Emerg Med 2019 Jan 23;19(1):13

 Background: Whether enhanced prehospital volume therapy leads to outcome improvements in severely injured patients with severe traumatic brain injury (TBI) remains controversial. The aim of this study was to investigate the influence of prehospital volume therapy on the clinical course of severely injured patients with severe TBI.

Methods: Data for 122,672 patients from TraumaRegister DGU® (TR-DGU) was analyzed. Inclusion criteria were defined as follows: Injury Severety Score (ISS) ≥ 16, primary admission, age ≥ 16 years, Abbreviated Injury Scale (AIS) head ≥3, administration of at least one unit of packed red blood cells (pRBCs), and available volume and blood pressure data. Stratification based on the following matched-pair criteria was performed: group 1: prehospital volumes of 0- 1000 ml; group 2: prehospital volumes of ≥1501 ml; AIS head (3, 4, 5 + 6 and higher than for other body regions); age (16-54, 55-69, ≥ 70 years); gender; prehospital intubation (yes/no); emergency treatment time +/- 30 min.; rescue resources (rescue helicopter, emergency ambulance); blood pressure (20-60, 61-90, ≥ 91 mmHg); year of accident (2002-2005, 2006- 2009, 2010-2012); AIS thorax, abdomen, and extremities plus pelvis.

Results: A total of 169 patients per group fulfilled the inclusion criteria. Increasing volume administration was associated with reduced coagulation capability and reduced hemoglobin (Hb) levels (prothrombin ratio: group 1: 68%, group 2: 63.7%; p ≤ 0.04; Hb: group 1: 11.2 mg/dl, group 2: 10.2 mg/dl; p ≤ 0.001). It was not possible to show a significant reduction in the mortality rate with increasing volumes (group 1: 45.6, group 2: 45.6; p = 1).

Conclusions: The data presented in this study demonstrates that prehospital volume administration of more than 1500 ml does not improve severely injured patients with severe traumatic brain injury (TBI).

Evaluation and Management of Sports-Related Lacerations of the Head and Neck

Andrew Hyden, Matthew Tennison

Curr Sports Med Rep 2020 Jan;19(1):24-28

Abstract

Soft tissue injuries to the head and neck are a common occurrence in sports. These anatomical regions are somewhat predisposed because of the "athletic stance" that is utilized in many close-contact sports. Although appropriate use of protective equipment, including mouth guards, helmets, and face shields, has reduced the incidence and severity of these injuries, they still occur regularly. To provide appropriate medical care, one must possess adequate knowledge of the superficial and deep anatomical structures, fundamental knowledge and skill in regard to wound care, and awareness of potential poor outcomes related to lacerations of unique structures, such as the mouth, eye, or ear.

Early management of severe pelvic injury (first 24 hours)

Pascal Incagnoli, Alain Puidupin, Sylvain Ausset, Jean Paul Beregi, Jacques Bessereau, Xavier Bobbia, Julien Brun, Elodie Brunel, Clément Buléon, Jacques Choukroun, Xavier Combes, Jean Stephane David, François-Régis Desfemmes, Delphine Garrigue, Jean-Luc Hanouz, Isabelle Plénier, Fréderic Rongieras, Benoit Vivien, Tobias Gauss, Anatole Harrois, Pierre Bouzat, Eric Kipnis

Anaesth Crit Care Pain Med 2019 Apr;38(2):199-207 

Objective: Pelvic fractures represent 5% of all traumatic fractures and 30% are isolated pelvic fractures. Pelvic fractures are found in 10 to 20% of severe trauma patients and their presence is highly correlated to increasing trauma severity scores. The high mortality of pelvic trauma, about 8 to 15%, is related to actively bleeding pelvic injuries and/or associated injuries to the head, abdomen or chest. Regardless of the severity of pelvic trauma, diagnosis and treatment must proceed according to a strategy that does not delay the management of the most severely injured patients. To date, in France, there are no guidelines issued by healthcare authorities or professional societies that address this subject.

Design: A consensus committee of 22 experts from the French Society of Anaesthesia and Intensive Care Medicine (Société Française d'Anesthésie et de Réanimation; SFAR) and the French Society of Emergency Medicine (Société Française de Médecine d'Urgence; SFMU) in collaboration with the French Society of Radiology (Société Française de Radiologie; SFR), French Defence Health Service (Service de Santé des Armées; SSA), French Society of Urology (Association Française d'Urologie; AFU), the French Society of Orthopaedic and Trauma Surgery (Société Française de Chirurgie Orthopédique et Traumatologique; SOCFCOT), and the French Society of Digestive Surgery (Société Française de Chirurgie digestive; SFCD) was convened. A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independently from any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised.

Methods: Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. The analysis of the literature and the recommendations were then conducted according to the GRADE® methodology.

Results: The SFAR Guideline panel provided 22 statements on prehospital and hospital management of the unstable patient with pelvic fracture. After three rounds of discussion and various amendments, a strong agreement was reached for 100% of recommendations. Of these recommendations, 11 have a high level of evidence (Grade 1 ± ), 11 have a low level of evidence (Grade 2 ± ).

Conclusions: Substantial agreement exists among experts regarding many strong recommendations for management of the unstable patient with pelvic fracture.

Medical Simulation-Based Learning Outcomes in Pre-Clinical Medical Education

 Maxwell J Jabaay, Dario A Marotta, Stephen L Aita, Dianne B Walker, Leah O Grcevich, Victor Camba, James R Nolin, James Lyons, John Giannini Jr 

Cureus. 2020 Dec 3;12(12):e11875 

Abstract 

Introduction Medical simulation is widely used in the United States medical curriculum. However, learning outcomes based on simulation have yet to be reported. In this study, we aim to characterize the objective performance of first- and second-year medical students following eight weeks of medical simulation-based learning. Methods First- (n=25) and second-year (n=15) medical students were recruited for this study. We designed and administered a novel pre-experience examination to collect participant demography and assess simulation and non-simulation knowledge. Following 14 high-fidelity simulation scenarios over the course of eight weeks, we administered an identical post-experience examination and compared performance, primarily using a within-subjects analytic design. Results Student performance improved by an average of 18% following the medical simulation experience, and first-year students demonstrated greater benefit (22%) as compared to second-years (12%). Relative to first-years, second-year students showed higher overall performance on both pre- and post-examination. Demographic factors and prior medical experience were not significantly associated with assessment performance and score improvement. Conclusions Our data supported the efficacy of simulation-based learning as evidenced by the significant improvement in objective performance on a standardized examination. That is, both first- and second-year medical students demonstrated test-score improvement following an eight-week medical simulation program. Of note, the first-year students exhibited greater benefit (at the group level). Importantly, these findings were statistically unrelated to participant demographic and background variables. Collectively, this study provides preliminary evidence that medical simulation in the pre-clinical phase of undergraduate medical education is an effective tool for student learning.

Evaluation of Safety and Efficacy of Prehospital Paramedic Administration of Sub-Dissociative Dose of Ketamine in the Treatment of Trauma-Related Pain in Adult Civilian Population

 Alex Jabourian, Fanglong Dong, Kevin Mackey, Reza Vaezazizi, Troy W Pennington, Michael Neeki

 Cureus. 2020 Aug 5;12(8):e9567 

Abstract 

Opiates are addicting and have a high potential for dependency. In the past decades, opiates remained the first-line pharmaceutical option of prehospital treatment for acute traumatic pain in the civilian population. Ketamine is an N-methyl-d-aspartate (NMDA) receptor antagonist that has analgesic properties and may serve as an alternative agent for the treatment of acute traumatic pain in prehospital settings. This study aims to assess the safety and efficacy of ketamine administration by paramedics in civilian prehospital settings for the treatment of acute traumatic pain. This was a prospective observational study in San Bernardino, Riverside and Stanislaus counties. Patients were included if they were > 15 years of age with complaints of traumatic or burn-related pain. Patients were excluded if they received opiates up to six hours prior to or concurrently with ketamine administration. The dose administered was 0.3 mg/kg intravenously over five minutes with a maximum dose of 30 mg. The option to administer a second dose was available to paramedics if the patient continued to have pain after 15 minutes following the first administration. Paired-T tests were conducted to assess the change in the primary outcome (pain score) and secondary outcomes (e.g. systolic blood pressure, pulse, and respiratory rate). P-value<0.05 was considered to be statistically significant. A total of 368 patients were included in the final analysis. The average age was 52.9 ± 23.1 years, and the average weight was 80.4 ± 22.2 kg. There was a statistically significant reduction in the pain score (9.13 ± 1.28 vs 3.7 ± 3.4, delta=5.43 ± 3.38, p<0.0001). Additionally, there was a statistically significant change in systolic blood pressure (143.42 ± 27.01 vs 145.65 ± 26.26, delta=2.22 ± 21.1, p=0.044), pulse (88.06 ± 18 vs 84.64 ± 15.92, delta= -3.42 ± 12.12, p<0.0001), and respiratory rate (19.04 ± 3.59 vs 17.74 ± 3.06, delta=-1.3 ± 2.96, p<0.0001). The current study suggested that paramedics are capable of safely identifying the appropriate patients for the administration of sub-dissociative doses of ketamine in the prehospital setting. Furthermore, the current study suggested that ketamine may be an effective analgesic in a select group of adult trauma patients.

Airway Clearance Using Suction Devices in Prehospital Combat Casualty Care: A Systematic Review

Priya Jain, Forhad Akhter, Austin Schoppe, R Lyle Hood, Robert A De Lorenzo

Prehosp Disaster Med. 2020 Dec;35(6):676-682 

Abstract 

Airway management is at the forefront for combat medics dealing with battlefield trauma. For military service members, compromised airways are the second leading cause of potentially survivable death on the battlefield, accounting for one in ten preventable combat deaths. Effective suction is a critical component of airway clearance. However, currently available devices are too heavy and bulky to be carried by combat medics and are insufficiently powered. The industry has not responded to the need, with companies continuing to produce models using 1970s technology. A literature review was completed with the assistance of a librarian. The databases searched included: Biomedical Research Database (BRD), Computer Retrieval of Information of Scientific Projects (CRISP), Federal Research in Progress (FEDRIP), Defense Technical Information Center (DTIC), Pub Med/Medline, and OVID. Additionally, a Google Scholar search was performed to identify nonstandard sources. After screening, a total of 40 articles were used. There were no randomized controlled trials or other high-quality evidence that addressed the issues; there was limited peer-reviewed literature on the use, effectiveness, adverse effects, and safety of suction for use in combat casualty care. A review of the available literature revealed no standards, either proposed, validated, or accepted, for the safety or avoidance of adverse effects for portable suction device use in combat casualty care. Similarly, there are no accepted standards to guide the safe use and anticipated adverse effects of suction for use in prehospital combat or emergency care. Nevertheless, there are meaningful data that can be extracted from the few studies available combined with non-clinical studies, narrative reviews and case reports, and expert opinions.

 

Estimating global injuries morbidity and mortality: methods and data used in the Global Burden of Disease 2017 study

Spencer L James, Chris D Castle, Zachary V Dingels, et al 

Inj Prev. 2020 Oct;26(Supp 1):i125-i153 

Background: While there is a long history of measuring death and disability from injuries, modern research methods must account for the wide spectrum of disability that can occur in an injury, and must provide estimates with sufficient demographic, geographical and temporal detail to be useful for policy makers. The Global Burden of Disease (GBD) 2017 study used methods to provide highly detailed estimates of global injury burden that meet these criteria. 

Methods: In this study, we report and discuss the methods used in GBD 2017 for injury morbidity and mortality burden estimation. In summary, these methods included estimating cause-specific mortality for every cause of injury, and then estimating incidence for every cause of injury. Non-fatal disability for each cause is then calculated based on the probabilities of suffering from different types of bodily injury experienced. 

Results: GBD 2017 produced morbidity and mortality estimates for 38 causes of injury. Estimates were produced in terms of incidence, prevalence, years lived with disability, cause-specific mortality, years of life lost and disability-adjusted life-years for a 28-year period for 22 age groups, 195 countries and both sexes. 

Conclusions: GBD 2017 demonstrated a complex and sophisticated series of analytical steps using the largest known database of morbidity and mortality data on injuries. GBD 2017 results should be used to help inform injury prevention policy making and resource allocation. We also identify important avenues for improving injury burden estimation in the future.

An Analysis of Conflicts Across Role 1 Guidelines

Sarah A Johnson, Ryann S Lauby, Andrew D Fisher, Jason F Naylor, Michael D April, Brit Long, Steven G Schauer

 Mil Med. 2020 Nov 24;usaa460. doi: 10.1093/milmed/usaa460. Online ahead of print.

 Introduction: Role 1 care is vital to patient survival and includes many echelons of care from point-of-injury first aid to medical attention at battalion aid stations. Many guidelines are written for Role 1 care providers to optimize care for different scenarios. Differences in the guidelines lead to confusion and discrepancies between the types of treatment medical care providers provide. Although the guidelines were written for different areas of care, uniformity between the guidelines is needed and will lead to a reduced mortality rate. 

Materials and methods: It was determined that the Tactical Combat Casualty Care Guidelines, Prolonged Field Care Guidelines, Joint Trauma System Clinical Practice Guidelines, and Standard Medical Operating Guidelines from medical evacuation were the military medical guidelines most relevant to Role 1 care. These Guidelines were compared side by side to determine the differences between them. 

Results: Although the guidelines were largely similar, many major differences were found between them. Our online tables contain large inconsistences between guidelines including direct contradictions in conversion of junctional tourniquets and the administration of tranexamic acid. 

Conclusions: Role 1 care is vital to patient survival, including care from point of injury to battalion aid stations, but the guidelines available to instruct this care and the guidance on which personnel should provide this care are conflicting. This lack of clarity and consistency may adversely impact treatment outcomes. The reduction or elimination of conflicting information across the various guidelines, augmentation of guidance for pediatric care, more specific guidance for unique levels of care, and clearer delineation of the Role 1 phases of care (as well as which guidelines are most appropriate to each) should be considered as urgent priorities within the military medical community.

Evaluation of I-Gel™ versus Classic LMA™ for Airway Management by Paramedics and Medical Students: A Manikin Study

Ashish Kumar Kannaujia, Uma Srivastava, Tapas Singh, Rudrashish Haldar 

Anesth Essays Res. Jan-Mar 2020;14(1):166-169 

Background and aim: Airway management is a lifesaving skill which all health-care workers should possess. Currently, most of the resuscitation councils recommend supraglottic airway devices as the technique of choice for airway management during cardiopulmonary resuscitation by health-care providers without expertise in tracheal intubation. This is because of its high first-pass success rate and easy to acquire and retain skill even by novices. 

Materials and methods: The present study was planned to compare the efficacy of two commonly available supraglottic airway devices, classic LMA (cLMA) and I-gel in securing airway in adult manikin by inexperienced persons (58 paramedics and 46 medical students), after a brief training. Our primary aim was to determine the first attempt success rate, and other parameters studied were the time and ease of insertion, overall success rate, and preference for device. 

Results: The first-attempt success rate of I-gel was higher in both groups of participants (74% in students and 69% in paramedicals) compared to that of cLMA (70% in l students and 53% in paramedics) although the overall success was the same. Majority of participants could secure airway quickly and easily by I-gel than by cLMA. More than 90% of participants preferred I-gel over cLMA. 

Conclusion: This study shows that inexperienced persons could learn to place the I-Gel and cLMA successfully in the manikin after a brief training in manikin. The first-attempt success rate and insertion of I-gel was easier and faster than that of cLMA by both groups of participants and most participants preferred I-gel due to ease of handling.

Gnana Laryngeal Airway in Clinical Practice: A Prospective Observational Study

Dheeraj Kapoor, Jasveer Singh, Sukanya Mitra, Omar Viswanath, Alan David Kaye, Ivan Urits, Vwaire Orhurhu 

Turk J Anaesthesiol Reanim. 2020 Aug;48(4):280-287 

Objective: The Gnana Laryngeal Airway (GLA) device, a novel supraglottic airway device, is similar to the LMA-Classic in basic design, but with an additional suction port on the convex portion of the laryngeal mask to remove the saliva. We evaluated the GLA device in terms of ease and time to insertion, the number of attempts, oropharyngeal leak pressure (OLP), correct placement, and complications in adult patients undergoing elective surgical procedures. 

Methods: After general anaesthesia, the GLA device was inserted in ASA Class I-II consecutive patients aged 18-60 years, who were scheduled for elective surgeries lasting <2h. An independent observer noted (1) 10 consecutive successful GLA device insertions, all on the first attempt; (2) 10 consecutive device insertions, each <20 second in duration; and (3) 10 consecutive patients with the mean leak <10%. The criteria were fulfilled in 50 consecutive patients. 

Results: In 72% of patients, the GLA device was successfully placed on the first attempt and was effortless in 64%. Between the first 10 and last 10 consecutive patients of the total 50, the ease-of-insertion grade progressively decreased (mean±standard deviation [SD]: 2.80±0.25 to 1.30±0.15, p<0.0001) and so did insertion time in seconds (28.70±1.87 to 14.20±0.79, p<0.0001). The post-insertion, OLP and airway compliance progressively increased, while the cuff inflation volume, peak airway pressure and airway resistance progressively decreased, along with minimal side effects and malposition. 

Conclusion: The GLA device insertion became progressively easier and faster; thus, such a device is promising and warrants further clinical evaluation.

The use of warm fresh whole blood transfusion in the austere setting: A civilian trauma experience

 Morihiro Katsura, Kazuhide Matsushima, Ryoichi Kitamura, Kyohei Kawasaki, Rei Takaesu, Shingo Fukuma, Masafumi Ie, Takahiro Murakami, Yoshitaka Asakura, Masato Uehara, Hidemitsu Mototake 

J Trauma Acute Care Surg. 2020 Sep;89(3):e28-e33 

Background: Hemostatic resuscitation strategy using blood components with a balanced ratio is adopted in the civilian trauma setting. However, there is usually limited availability of blood components in the austere setting. Warm fresh whole blood (WFWB) has been used for trauma patients with life-threatening hemorrhage necessitating massive transfusions in the Okinawa Islands, Japan. The purpose of this study was to evaluate the safety and feasibility of WFWB use in the austere civilian trauma setting. 

Methods: We conducted a retrospective cohort study between January 1999 and June 2019, including trauma patients who received WFWB within 24 hours of admission. Immediately after WFWB was collected from blood donors, the sample was typed and screened for transmissible infectious diseases. Approximately half of the study population received irradiated WFWB to prevent graft versus host disease. We evaluated the incidence of transfusion-associated adverse events. Transfusion requirements and patient outcomes were compared between early and late WFWB use. 

Results: A total of 28 patients from three civilian institutions were eligible. Of those, 93% sustained blunt trauma. The median Injury Severity Score was 37 (interquartile range, 32-49). All patients required operative hemostatic intervention, and half of the patients required both operative and endovascular hemostatic interventions. Patients received a median of 1,800 mL WFWB transfusions from seven volunteer blood donors. None of our subjects developed hemolytic reactions, transmissible infectious diseases, or graft versus host disease. Early WFWB use (within 4 hours of admission) was associated with a significant reduction in platelet transfusion requirement compared with the late WFWB group in univariate analysis (16 units vs. 47 units, p = 0.002). 

Conclusion: Warm fresh whole blood use is safe and feasible in an austere civilian trauma setting. Prospective studies with larger cohorts are necessary to determine whether early WFWB use will affect patient outcomes, transfusion requirement, and treatment cost.

Efficacy of tranexamic acid in patients with traumatic brain injury

Tomoyuki Kawada 

EXCLI J. 2020 Dec 8;19:1547-1548 

No abstract available

Should Albumin be Considered for Prehospital Resuscitation in Austere Environments? A Prospective Randomized Survival Study in Rabbits

Bijan S Kheirabadi, Nahir Miranda, Irasema B Terrazas, Amber N Voelker, Rodolfo de Guzman, Nathan A Wienandt, Ammon W Brown, Michael A Dubick 

Shock. 2020 Sep;54(3):358-367 

Background: The new guidelines for prehospital care of combat casualties in shock recommend administration of whole blood or blood components to increase blood pressure to a permissible hypotensive level (i.e., hypotensive resuscitation [HR]). We investigated if 2 h of HR using limited volumes of whole blood, plasma, or albumin would lead to full recovery and long-term survival of rabbits subjected to severe hemorrhagic shock (HS). 

Methods: Following instrumentation, laparotomy was performed on IV-anesthetized spontaneously breathing New Zealand white rabbits (3.0 kg -3.5 kg). Next, ∼40% of rabbits' blood volume was removed producing HS (mean arterial pressure [MAP]∼20 mm Hg). Fifteen minutes later, rabbits were resuscitated with a limited volume (12.5 mL/kg) of rabbit whole blood (fresh whole blood [FWB]), rabbit fresh frozen plasma (FFP), or 5% human albumin (ALB) to a target pressure (MAP) of 60 mm Hg (n=8/grp) and monitored for 2 h. Liver bleeding time was measured at baseline and 10 min after HR. Subsequently, animals were fully resuscitated (blood + lactated Ringer [LR]), surgically repaired, and recovered for 8 days. An untreated group (n = 6) was also included. 

Results: Following HS, lactate and base deficit levels were increased to 8.2 ± 1.6 and 12.9 ± 3.1 mM respectively with no difference among groups. A lower volume of FWB volume was required to reach the target MAP (P < 0.05 vs. ALB) but MAP declined during the HR period (P < 0.01 vs. ALB). FWB provided higher hematocrit and platelets but it did not reduce lactate level faster than other fluids. Beside higher fibrinogen, no differences were found in hemostatic or resuscitative effects of FFP versus ALB. Bleeding time was prolonged with ALB and FFP fluids but unchanged with FWB. Untreated rabbits died during shock or shortly after. All treated rabbits except one recovered and lived for 8 days with normal blood tests and similar tissue histology. 

Conclusions: Two hours of HR using a limited volume of FWB, FFP, or ALB led to full recovery and long-term survival of rabbits subjected to HS. Apart from bleeding time, no clinically significant differences were found among the three fluids. Five percent human albumin solutions are isotonic, iso-oncotic, ready-to-use, stable, and compatible with all blood types and should be considered for prehospital resuscitation where blood products are not available or not accepted.

Military Acute Concussion Evaluation: A Report on Clinical Usability, Utility, and User's Perceived Confidence

Bilal Khokhar, Kendra Jorgensen-Wagers, Donald Marion, Seth Kiser

J Neurotrauma. 2021 Jan 15;38(2):210-217

Abstract 

The signs and symptoms of concussion may not always be clear. Therefore, the Military Acute Concussion Evaluation (MACE) tool was created to help deployed medics and corpsmen identify concussions, particularly in deployed settings. Since 2008, the MACE has been updated multiple times, but each new version of the tool is more complex and takes longer to complete. The objective of this study was to assess the usability, utility, and perceived confidence among military healthcare providers for the latest version, MACE 2. Therefore, a semi-structured interview, including Likert-scale and open-ended questions, was conducted among military healthcare providers at Landstuhl Regional Medical Center in order to assess the usability, utility and perceived confidence of the MACE 2. All of the providers had completed a training course on the MACE 2 and had used it for at least 3 months in their clinics. A total of 28 participants were recruited, including 22 medics, two physicians, three nurses, and one physician assistant. Average scores of usability, utility, and confidence were 5.7, 6.6, and 6.3, respectively, with 7.0 being the most positive score, and thus indicating positive assessments in all categories. The open-ended questions revealed high usability and confidence and the desire for additional training on the tool. In conclusion, despite the increased complexity and duration of the MACE 2 compared with the previous version of this tool, military providers and army medics found the new MACE 2 very useable and had a high degree of confidence in its performance.

Effectiveness of kaolin-impregnated hemostatic gauze use in preperitoneal pelvic packing for patients with pelvic fractures and hemodynamic instability: A propensity score matching analysis

Kwangmin Kim, Hongjin Shim, Pil Young Jung, Seongyup Kim, Young Un Choi, Keum Seok Bae, Jung Kuk Lee, Ji Young Jang 

PLoS One. 2020 Jul 24;15(7):e0236645. doi: 10.1371/journal.pone.0236645. eCollection 2020. 

Introduction: We evaluated the effectiveness of kaolin-impregnated hemostatic gauze use in preperitoneal pelvic packing (PPP) for patients with hemodynamic instability due to severe pelvic fractures. 

Materials and methods: Between May 2014 and October 2018, 53 of 75 patients who underwent PPP due to hemodynamic instability induced by pelvic fracture were enrolled. Their medical records were prospectively collected and retrospectively analyzed. QuikClot combat gauze (hydrophilic gauze impregnated with kaolin) and general surgical tape were used in 21 patients, while general surgical tape was used in the remaining 32 patients. 

Results: As there were differences in the characteristics of patients between the hemostatic gauze (HG) group and control group, propensity score matching (PSM) was performed to adjust for age, sex, and lactate levels. After PSM, the clinical characteristics between the two groups became similar. There were no differences in the rates of mortality and hemorrhage-induced mortality between the two groups. However, the packed red blood cell (RBC) requirement for an additional 12 hours in the HG group was significantly lower than that in the control group (4.1 ± 3.5 vs. 7.6 ± 6.1 units, p = 0.035). The lengths of intensive care unit and hospital stays tended to be shorter in the HG group than in the control group (11.6 vs. 18.5 days, p = 0.1582; 30.8 vs. 47.4 days, p = 0.1861, respectively). 

Conclusions: The use of HG during PPP did not reduce hemorrhage-induced mortality, but did reduce the need for additional packed RBC transfusions in patients with hemodynamic instability due to severe pelvic fractures.

Minimally Invasive Treatment Options for Managing Spontaneous Intracerebral Hemorrhage

Michael Kim, Jared Cooper, Fawaz Al-Mufti, Chirag Gandhi, Christian Bowers

Cardiol Rev. Jan/Feb 2021;29(1):5-9 

Abstract 

Spontaneous intracerebral hemorrhage (SICH) is a common stroke subtype, accounting for 10-35% of all stroke. It is the most disabling subtype as well, with disproportionately high rates of morbidity and mortality. Despite numerous advances in neurocritical care and stroke management, the prognosis remains poor, and no medical or surgical interventions have been shown to significantly reduce mortality or improve outcomes. Surgical evacuation of SICH has many theoretical benefits, such as reducing secondary injury, reducing intracranial pressures, and preventing cerebral herniation. However, trials involving open craniotomy for SICH evacuation have not yielded significant clinical benefit, and one thought is that benefit is not seen due to injury to the overlying healthy brain tissue. Therefore, minimally invasive options have increasingly been studied as an option to evacuate the SICH while minimizing injury to healthy tissue. We present here a select review of various minimally-invasive techniques for the evacuation of SICH.

Leaning forward: Early arterial access promotes resuscitative endovascular balloon occlusion of the aorta utilization in battlefield casualties

Brian Scott Knipp, Kenneth Eugene Needham, Phu Tan Nguyen, Meaghan Patricia Keville, Jason Thomas Brzuchalski, Charlie Srivilasa, Clayton Jon Lewis, Richard David Betzold, Joseph Jeremy DuBose 

J Trauma Acute Care Surg. 2020 Aug;89(2S Suppl 2):S88-S92 

Abstract 

Uncontrolled noncompressible torso hemorrhage remains a leading cause of potentially preventable death on the battlefield. The utilization of resuscitative endovascular balloon occlusion of the aorta (REBOA) has gained considerable traction in civilian and military trauma care. Establishment of arterial access remains the rate-limiting step in endovascular aortic occlusion. The decision to place arterial access, including size, location, and the appropriate clinician and scenario all must be considered to achieve the optimal patient outcome. This report is submitted by the Joint Medical Augmentation Unit, an elite surgical/resuscitation team that provides medical care in the most far-forward, austere environments in the special operations community. The authors highlight two cases where early arterial access, REBOA utilization, and massive blood transfusion with damage-control surgery were associated with patient survival. We also address the prehospital application of REBOA in battlefield trauma. LEVEL OF EVIDENCE: Special Report, Level V.

Neck cooling induces blood pressure increase and peripheral vasoconstriction in healthy persons

Julia Koehn, Ruihao Wang, Carmen de Rojas Leal, Bernd Kallmünzer, Klemens Winder, Martin Köhrmann, Rainer Kollmar, Stefan Schwab, Max J Hilz 

Neurol Sci. 2020 Sep;41(9):2521-2529 

Introduction: Noninvasive temperature modulation by localized neck cooling might be desirable in the prehospital phase of acute hypoxic brain injuries. While combined head and neck cooling induces significant discomfort, peripheral vasoconstriction, and blood pressure increase, localized neck cooling more selectively targets blood vessels that supply the brain, spares thermal receptors of the face and skull, and might therefore cause less discomfort cardiovascular side effects compared to head- and neck cooling. The purpose of this study is to assess the effects of noninvasive selective neck cooling on cardiovascular parameters and cerebral blood flow velocity (CBFV). 

Methods: Eleven healthy persons (6 women, mean age 42 ± 11 years) underwent 90 min of localized dorsal and frontal neck cooling (EMCOOLS Brain.Pad™) without sedation. Before and after cooling onset, and after every 10 min of cooling, we determined rectal, tympanic, and neck skin temperatures. Before and after cooling onset, after 60- and 90-min cooling, we monitored RR intervals (RRI), systolic, diastolic blood pressures (BPsys, BPdia), laser Doppler skin blood flow (SBF) at the index finger pulp, and CBFV at the proximal middle cerebral artery (MCA). We compared values before and during cooling by analysis of variance for repeated measurements with post hoc analysis (significance: p < 0.05). 

Results: Neck skin temperature dropped significantly by 9.2 ± 4.5 °C (minimum after 40 min), while tympanic temperature decreased by only 0.8 ± 0.4 °C (minimum after 50 min), and rectal temperature by only 0.2 ± 0.3 °C (minimum after 60 min of cooling). Index finger SBF decreased (by 83.4 ± 126.0 PU), BPsys and BPdia increased (by 11.2 ± 13.1 mmHg and 8.0 ± 10.1 mmHg), and heart rate slowed significantly while MCA-CBFV remained unchanged during cooling. 

Conclusions: While localized neck cooling prominently lowered neck skin temperature, it had little effect on tympanic temperature but significantly increased BP which may have detrimental effects in patients with acute brain injuries.

The accuracy of preliminary diagnoses made by paramedics - a cross-sectional comparative study

Outi Koivulahti, Miretta Tommila, Elina Haavisto 

Scand J Trauma Resusc Emerg Med. 2020 Jul 23;28(1):70 

Background: Clinical decision-making skills of paramedics have been emphasized because of the growing complexity of emergency medicine nursing. A preliminary diagnosis made by a paramedic has an essential role in directing the subsequent care. An accurate preliminary diagnosis improves the patient's outcome. The research in this area is relatively scarce and there are no previous studies in Finland describing the accuracy of preliminary diagnoses made by paramedics. The aim of this study was to evaluate whether paramedics are making accurate preliminary diagnoses for the patients they are transporting to hospital. In addition, the aim was to describe the variables related to an accurate preliminary diagnosis. 

Methods: A cross-sectional comparative approach was used and conducted through a questionnaire to gather data from the paramedics. A total of 71 paramedics participated in the study and 378 patient cases were included. The paramedics were asked to describe the basic information of a case, to state their preliminary diagnosis, and give their own educational background. The accuracy of the paramedic's preliminary diagnosis was compared with the discharge diagnosis of the ED physicians retrieved from hospital's patient records. Logistic regression analysis and a binomial test were used to test the statistical significance. 

Results: The agreement between the paramedics' preliminary diagnosis vs. hospital diagnosis was 70% (n = 261). Diagnostic accuracy varied according to the medical condition from mental diseases and intoxication (86%, p = 0,000), cerebral strokes (81%, p = 0,007) to infections (31% p = 0,029). The educational background of a bachelor-degree-level paramedic (p = 0,016, 95% Cl 1,7-139,6) and a good self-assessment value (p = 0,003, 95% Cl 1,2-2,7) were related to making a correct diagnosis. 

Conclusions: Paramedics are able to determine preliminary diagnoses at satisfactory level. The relationship between educational background and diagnostic accuracy suggests that there is a definitive need for a specific pre-hospital nursing education.

A study of the pharmacokinetics of moxifloxacin by the dynamics of its distribution in the blood plasma and saliva of healthy volunteers: a comparative analysis and possible extrapolation methods

Svetlana N Kondratenko, Irina V Zolkina, Eugenia V Shikh 

Drug Metab Pers Ther. 2020 Sep 2;/j/dmdi.ahead-of-print/dmdi-2020-0115/dmdi-2020-0115.xml. doi: 10.1515/dmdi-2020-0115. Online ahead of print. 

Abstract 

Objectives The pharmacokinetics of moxifloxacin in plasma and saliva was investigated in this study. Methods The pharmacokinetics of two specialty drugs of moxifloxacin - reference (Ref) and test (Test) preparation - was studied in 18 healthy volunteers after a single oral dose of 400 mg. Results It was found that the concentration of moxifloxacin in saliva 3-24 h after taking the drugs was statistically significantly higher than that in plasma. A high correlation was observed between the concentration of moxifloxacin in plasma and saliva of volunteers after taking of Ref and Test. Some pharmacokinetic parameters, calculated by the concentration of moxifloxacin in saliva and plasma, are statistically different. A technique is proposed for extrapolating the concentration of moxifloxacin in plasma according to its concentration in saliva using the established linear relationship between the moxifloxacin in plasma and saliva of volunteers in time interval of 3-24 h after taking Ref. Based on the obtained extrapolated concentration of moxifloxacin, the pharmacokinetic parameters were calculated for two studied drugs and did not statistically differ from the parameters calculated according to the data in plasma. Conclusions The developed method of concentration extrapolation allows the use of saliva for pharmacokinetic studies of the tablet preparations of moxifloxacin.

 

Pediatric Prehospital Airway Management by U.S. Forces in Iraq and Afghanistan

Elizabeth A Koslow, Matthew A Borgman, Michael D April, Steven G Schauer 

Mil Med. 2020 Sep 18;185(9-10):e1435-e1439 

Introduction: Airway obstruction is a treatable cause of potentially preventable death on the battlefield. Emergency cricothyrotomies are rarely performed in developed countries, but are a common prehospital procedure in recent conflicts in Iraq and Afghanistan. We describe prehospital airway interventions performed on pediatric casualties with a focus on cricothyrotomy during these recent conflicts. 

Materials and methods: This is a secondary analysis of previously published dataset from the Department of Defense Trauma Registry for pediatric encounters from January 2007 to January 2017. Within our dataset we searched for all instances of airway interventions in the prehospital setting. 

Results: During this time, there were 3,439 pediatric casualties in the registry with a total of 18 prehospital cricothyrotomies and 211 prehospital intubations. For cricothyrotomies, the median age was 10 years, most (72.2%) were male, median composite injury score was 25, most were injured by explosive (44.4%), more commonly located in Afghanistan (77.8%), and approximately half survived to hospital discharge (44.4%). The head was most frequently injured (44.4%). Of those undergoing endotracheal intubation, the median age was 10 years, most (75.8%) were male, median injury score was 17, most were injured by explosives (53.5%), most were in Afghanistan (85.7%), and most survived to hospital discharge (66.8%). The head/neck most frequently had a serious injury (56.8%). 

Conclusions: In this dataset, 6.8% of children underwent prehospital intubation and 0.5% underwent prehospital cricothyrotomy. Airway interventions were frequently associated with head injuries. This highlights the importance of training and equipping prehospital medical personnel for pediatric trauma care in accordance with military clinical practice guidelines.

Conversion: Simulated Method of Exchanging Tourniquet Use for Pressure Dressing Use

John F Kragh Jr, James K Aden 3rd, Michael A Dubick 

J Spec Oper Med. Fall 2020;20(3):44-51 

Background: Given little data to assess guidelines, we sought a way to exchange one type of intervention, field tourniquet use, for another, use of a pressure dressing. The study purpose was to test performance of controlling simulated bleeding with a stepwise procedure of tourniquet conversion. 

Methods: An experiment was designed to assess 15 tests of a caregiver making tourniquet-dressing conversions. Tests were divided into trials: tourniquet use and its conversion. In laboratory conditions, the tourniquet trial was care under gunfire; then, the conversion trial was emergency healthcare. A HapMed Leg Tourniquet Trainer simulated a limb amputation. An investigator provided healthcare. 

Results: Mean (± standard deviation [SD]) test time and blood loss were 9 ± 3.6 minutes and 334 ± 353.9mL, respectively. The first test took 17 minutes. By test number, times decreased; the last six took ≤7 minutes. All tourniquet trials controlled bleeding. Mean (±SD) tourniquet pressure and blood loss were 222 ± 18.0mmHg and 146 ± 40.9mL, respectively. Bleeding remained uncontrolled in one conversion. Initial attempts to wrap a dressing were effective in 73% of tries (n = 11 of 15). Four of 15 wrap attempts (27%) were repeated to troubleshoot bleeding recurrence, and the first three tests required a repetition. Mean (±SD) dressing pressures and blood losses were 141 ± 17.6mmHg and 188 ± 327.4mL, respectively. Unsatisfactory conversion trials had a dressing pressure <137mmHg. Dressings and wraps hid the wound to impair assessment of bleeding. 

Conclusions: In testing a method of converting a limb tourniquet to a pressure dressing, the caregiver performed faster with experience accrual. The tourniquet results were uniformly good, but conversion results were worse and more varied. Simulating conversion was disappointing on a manikin and indicated that its redesign might be needed to suit this method. The procedural method constituted a start for further development.

Effects of Donning and Wearing Personal Protective Equipment on Tourniquet Use and Conversion

John F Kragh Jr, Tuan D Le, Michael A Dubick 

J Spec Oper Med. Winter 2020;20(4):40-46 

Background: We sought to gather data about the effects of personal protective equipment (PPE) use on tourniquet interventions by preliminarily developing a way to simulate delay effects, particularly on time and blood loss. Such knowledge might aid readiness. Field calls to emergency departments may indicate donning of PPE before patient arrival. The purpose of this study was to investigate (1) delay effects of donning the PPE studied on field-tourniquet control of hemorrhage and (2) delay effects of wearing the PPE on application of a field tourniquet and its conversion to a pneumatic tourniquet. 

Methods: The experiment simulated 30 tests of nonpneumatic field tourniquet use (http://www.combattourniquet.com/wp -content). The research intervention was the use of PPE. Data were grouped. The control group had no PPE (PPE0). PPE1 and PPE2 groups had mostly improvised and off-the-shelf equipment, respectively. PPE1 included donning a coat, goggles, face covering, cap, booties, and gloves. PPE2 had analogous items. The group order was randomized. A test included paired trials: field tourniquet, followed by conversion. An investigator simulated the caregiver. A task trainer simulated a thigh amputation. Donning delays were evaluated as differences in mean times to stop bleeding compared with PPE0. Blood loss results from donning PPE were calculated as the delay multiplied by its bleeding rate, 500mL/min. 

Results: PPE0 had no delay: its mean blood loss was 392mL. PPE1 had 805mL more blood loss than PPE0 did. PPE2 exceeded PPE0 by 1004mL. Donning time (blood loss) for PPE1 and PPE2 were 1.4 minutes (712mL) and 1.7 minutes (863mL), respectively. The wearing of PPE did not slow down field tourniquet application or its conversion. 

Conclusions: How long it took to don PPE delayed the time to stop bleeding and increased blood loss, but wearing PPE slowed down neither field tourniquet application nor its conversion.

Managing and securing the bleeding upper airway: a narrative review

 Michael Seltz Kristensen, Barry McGuire 

Can J Anaesth. 2020 Jan;67(1):128-140 

Abstract 

Failure to manage bleeding in the airway is an important cause of airway-related death. The purpose of this narrative review is to identify techniques and strategies that can be employed when severe bleeding in the upper airway may render traditional airway management (e.g., facemask ventilation, intubation via direct/video laryngoscopy, flexible bronchoscopy) impossible because of impeded vision. An extensive literature search was conducted of bibliographic databases, guidelines, and textbooks using search terms related to airway management and bleeding. We identified techniques that establish a definitive airway, even in cases of impeded visibility resulting from severe bleeding in the airway. These include flexible video-/optical- scope-guided intubation via a supraglottic airway device; cricothyroidotomy or tracheotomy; and retrograde-, blind nasal-, oral-digital-, light-, and ultrasound-guided intubation. We provide a structured approach to managing bleeding in the airway that accounts for the source of bleeding and the estimated risk of failure to intubate using direct laryngoscopy or to achieve a front-of-neck access for surgical airway rescue. In situations where these techniques are predicted to be successful, the recommended approach is to identify the cricothyroid membrane (in preparation for rescue cricothyroidotomy), followed by rapid sequence induction. In situations where traditional management of the airway is likely to fail, we recommend an awake approach with one of the

aforementioned techniques.

Current state of whole blood transfusion for civilian trauma resuscitation

Bryon Jackson, Colin Murphy, Magali J Fontaine 

Transfusion 2020 Jun;60 Suppl 3:S45-S52 

Background: Whole blood (WB) is rapidly emerging as the treatment modality of choice for the initial resuscitation of civilian trauma patients across the United States. The reemergence of WB has been rapid and driven in part by recognition of the importance of early plasma transfusion in the resuscitation process.

Study design and methods: The study was designed as a critical analysis of the available literature on WB transfusion in civilian trauma patients. Studies were included if they reported on transfusion of cold-stored WB used in a civilian setting and measured safety, feasibility, or a direct clinical outcome.

Results: Examination of the available literature supports the feasibility and safety of WB used in treatment of civilian trauma patients. The evidence regarding clinical outcomes, particularly with direct comparison to equivalent doses of component therapy, is more limited. The literature is predominantly descriptive and retrospective in nature and limited by the heterogeneity of clinical WB protocols being used. Based on this limited data set, there are limited conclusions that can be used to definitely support or refute the clinical superiority of WB to component therapy.

Conclusion: Current literature supports the safety and feasibility of WB, but prospective randomized trials comparing WB to component therapy are needed to provide the definitive evidence on this topic.

Demographics and Mortality Rates of Surgical Emergencies Treated at the Casualty Operation Theater: A Six-month Retrospective Analysis

Salman Jafferi, Ghina Awais, Rubiya Naeem, Jabbar Ghufran Syed, Muhammad Ali Jr, Hamra Afridi, M Hassan, Shahid Rasul 

Cureus. 2020 Apr 13;12(4):e7658  

Introduction: Emergencies such as appendicitis, peritonitis, road traffic accidents and gunshots require immediate surgical intervention. Patients are first resuscitated at the emergency department and then shifted to the casualty operation theater (COT). COT is a state-of-the-art operation theater that is open 24/7 and ready to deal with any surgical crisis. Once surgery is performed, the patients are admitted to the surgical ward for post-operative care. Jinnah Postgraduate Medical Centre (JPMC) is the largest tertiary care hospital in Karachi. There is very limited data on the cases that are dealt with on regular basis at the COT in JPMC. Here we break the mold and analyze the various aspects of surgical emergencies treated at the COT over the course of last six months. Objectives To evaluate the demographics and mortality rates of emergencies treated at the COT in the last six months. Methods This was a retrospective study, held for six months (July 1st 2019 to December 31st 2019). Data was obtained from the Records and Administration section, Surgical Unit IV (ward 21), Jinnah Postgraduate Medical Centre. Results Three hundred and fifty-five patients were inducted into the study, predominantly male. Majority (71.54%) of the referrals were made from within the city. The mean age of the patients was 48.57 ± 14.92 years. Appendicitis was the most common emergency treated at the COT. The overall mortality rate was 23.94%. Peritonitis and road traffic accidents contributed significantly to the mortality rate. Conclusion Surgical emergencies treated at the COT have a high mortality rate at one week. Prompt recognition, early referrals and intervention can help reduce mortality in the future.

Platelet Function: Meloxicam Intravenous in Whole Blood Samples From Healthy Volunteers

Jonathan S Jahr, Shawn Searle, Stewart McCallum, Randall Mack, Kim Minger, Alex Freyer, Wei Du, Sue Hobson

Clin Pharmacol Drug Dev 2020 Jan 21. Online ahead of print. 

Abstract

Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective treatments for pain but may induce bleeding events due to platelet dysfunction associated with inhibition of cyclooxygenase (COX)- 1 impairing thromboxane production. An intravenous nanocrystal formulation of meloxicam, a COX-2 preferential nonsteroidal anti-inflammatory drug, is under development for the treatment of moderate to severe pain. This single-center ex vivo study evaluated the effect of meloxicam intravenous and ketorolac on platelet function in whole blood samples from healthy volunteers. Each whole blood sample was aliquoted to allow analysis using a platelet function analyzer under negative control (untreated), positive control (2 therapeutic ketorolac concentrations), and meloxicam intravenous (1 therapeutic, 3 supratherapeutic concentrations) using both collagen with epinephrine and collagen with adenosine diphosphate reagent cartridges. The platelet function analyzer determines closure time by simulating platelet adhesion and aggregation following vascular injury. The final analysis set included data from 8 subjects. The collagen with adenosine diphosphate analysis (sensitive to thrombocytopathies) showed no significant differences in closure time for meloxicam- or ketorolac-treated samples and untreated control.

The collagen with epinephrine analysis (sensitive to aspirin-induced platelet abnormalities) produced no significant difference in closure time between any meloxicam concentration and untreated control. Ketorolac was associated with significantly longer closure times vs untreated control at both the 2.5- and 5-µg/mL concentrations (P = .003 and .0257, respectively) and vs meloxicam at several concentrations. Similar results were observed when all analyzed samples were included. Meloxicam intravenous had no significant effect on closure times at therapeutic or supratherapeutic concentrations in this ex vivo study.

The effects of QuikClot Combat Gauze and Celox Rapid on hemorrhage control

Don Johnson, Michelle Johnson

Am J Disaster Med 2019 Winter;14(1):17-23 

Abstract

Objective: Compare QuikClot Combat Gauze (QCG) and Celox Rapid (CR) for initial hemostasis and over a 1-hour period.

Design: Experimental study.

Setting: Approved animal laboratory.

Subjects: Twenty-one Yorkshire swine.

Interventions: Subjects were randomly assigned to either the QCG (n = 11) or CR (n = 10) group. An arteriotomy was made in the right femoral artery with a 6-mm vascular punch.

Bleeding was allowed for 45 seconds. QCG or CR was applied followed by firm pressure for 3 minutes according to Committee on Tactical Combat Casualty Care guidelines. A 10-pound weight simulating a pressure dressing was applied, and the wound was observed for 1 hour. Dressing failure was bleeding > 2 percent of blood volume.

Main outcome measures: Achievement and maintenance of hemostasis and amount of hemorrhage during observation. Odds of successful hemostasis.

Results: QCG was significantly better than CR in initial hemostasis (p = 0.049) and maintaining hemostasis over 1 hour (p = 0.020). One hundred percent of QCG subjects and 70 percent of CR subjects achieved initial hemostasis. During the 1-hour observation, one additional CR subject failed to maintain hemostasis. CR had significantly more hemorrhage than QCG during the 1-hour observation (p = 0.027). QCG had no bleeding compared to CR that had a mean of 162 ± 48 mL (standard error of mean) over 2 minutes. QCG had 15.9 times greater odds of success compared to CR over a period of 1 hour. Over the 1-hour observation time, 100 percent of QCG achieved hemostasis compared to 60 percent of CR.

Prehospital Whole Blood in SOF: Current Use and Future Directions

Thomas B Jones, Virgil L Moore, Akira A Shishido

J Spec Oper Med Winter 2019;19(4):88-90. 

Abstract

The US Joint Trauma System (JTS) recommends stored whole blood (SWB) as the preferred product for prehospital resuscitation of battlefield casualties in both their Tactical Combat Casualty Care (TCCC) guidelines and their clinical practice guidelines (CPGs). Clinical data from nearly 2 decades of war during Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) suggest that whole blood (WB) is safe, effective, and far superior to crystalloid and colloid resuscitation fluids. The JTS CPG for whole blood transfusion reflects the most recent clinical evidence but poses unique challenges for execution by Special Operations Forces (SOF) operating in austere environments. Given the limited shelf-life of 35 days, WB requires a constant steady pool of donors. Additionally, the cold-chain requirement for storage poses challenges for SOF on long missions without access to blood refrigerators. SOF operating in less-developed theaters face additional logistical challenges. To mitigate the challenges of WB delivery, US SOF have implemented various protocols to ensure optimal donor pool, awareness/education among medics and specialized equipment for tactical methods of blood-carry and delivery. In general, steps taken include the following: (1) Prior to deployment, soldiers are screened for blood type and titers in order to establish a large donor pool. Support soldiers have been found to be particularly beneficial donors as they typically are in closer proximity to the blood support detachment. (2) In units that operate in smaller teams, such as ODAs, medics are outfitted with "blood kits" to carry blood on missions for point of injury transfusion. In units with larger teams, LTOWB donors are identified on missions and deliver fresh WB in the event of casualties. (3) Medics receive a WB transfusion refresher tabletop exercise and review after action reviews from previous rotations. Additionally, prehospital WB delivery is a required component of scenario-based premission training. The expectation is that medics will administer WB on missions when tactically feasible. Using the prolonged field care framework (ruck, truck, house) as a template, medics now use different methods to store and transport the SWB depending on phase. Medic "truck" and "house" kits include the Dometic CFX™ powered coolers that run on AC, DC, or solar power and allow for constant temperature monitoring. When on foot, medics have been outfitted with tactical blood coolers including the Pelican Biomedical Medic 4™ or Combat Medical Blood Box™ along with a Belmont Buddy- Lite™ intravenous (IV) infusion warmer and IV administration kit with standard micron filter.

Presently, SOF medics have the donor support, logistical framework, training, and equipment to deliver WB at the point of injury. However, widespread implementation will require expanded distribution and standardization of "blood kits." Additionally, SOF medical planners must put greater emphasis on education and the importance of WB over crystalloids or colloids-as many medics continue to carry only these products out of convenience. As SOF strive to establish tactics, techniques, and procedures (TTPs) and streamline prehospital WB delivery, we must constantly reassess and refine our procedures, incorporate the latest evidence and technology, and adapt to an evolving battlefield.

BET 1: cervical spine immobilisation in the management of drowning victims

Tom Jones, Alistair Rennie

Emerg Med J 2019 Dec;36(12):766-767 

Abstract

A short cut review was carried out to establish whether patients presenting to the emergency department after a near drowning should have cervical spine immobilisation. A search of the literature found only three studies directly relevant to the question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The clinical bottom line is that cervical spine injuries are rare in drowning and near drowning unless there is a history of diving or a fall or signs of trauma. Cervical spine immobilisation should be reserved for cases where there is a reasonable suspicion of a spinal injury.

Improving survival after an emergency resuscitative thoracotomy: a 5-year review of the Trauma Quality Improvement Program

Bellal Joseph, Muhammad Khan, Faisal Jehan, Rifat Latifi, Peter Rhee

Trauma Surg Acute Care Open 2018 Oct 9;3(1):e000201 

Abstract

Background: Advancement in trauma care has led to the evolution of emergency resuscitative thoracotomy (ERT) for the revival of trauma patients. We now have more precise understanding of selecting suitable patients for achieving optimal outcomes. The aim of our study was to analyze the utilization and survival trends during the past 5 years, as well as factors that influence survival after ERT.

Methods: A 5-year (2010-2014) analysis of all trauma patients ≥18 years who underwent ERT in the American College of Surgeons Trauma Quality Improvement Program. Outcome measures were utilization rates and survival trends after ERT during the 5-year period.

Regression analysis was performed.

Results: 2229 patients underwent ERT, mean age was 37±17 years, 81% were male. Overall 56% patients had penetrating mechanism, location of major injury was thorax in 48, and 71% had signs of life (SOL) on arrival. The overall survival rate was 9.6%. From 2010-2014 ERT utilization has decreased from 331/100 000 to 243/100 000 trauma admissions (p=0.002) and the survival rate has improved from 7.9% to 11.3% (p<0.001). On regression, the independent predictors of survival were penetrating mechanism, age<60 years, SOL on arrival, no prehospital CPR and ISS. No patient aged >60 years with a blunt mechanism of injury (MOI) survived, and there were no survivors above the age of 70 years, regardless of injury mechanism.

Discussion: Utilization of ERT has been decreased during the study period along with improved survival rates. The results of our study demonstrate that performing ERT on patients aged >60 years with a blunt MOI or on any patient aged ≥70 years, regardless of MOI, is futile and should be avoided.

Level of evidence: Level III, prognostic studies.

French lyophilized plasma versus normal saline for post-traumatic coagulopathy prevention and correction: PREHO-PLYO protocol for a multicenter randomized controlled clinical trial

Daniel Jost, Sabine Lemoine, Frederic Lemoine, Vincent Lanoe, Olga Maurin, Clément Derkenne, Marilyn Franchin Frattini, Maëlle Delacote, Edouard Seguineau, Anne Godefroy, Nicolas Hervault, Ludovic Delhaye, Nicolas Pouliquen, Emilie Louis-Delauriere, Julie Trichereau, Florian Roquet, Marina Salomé, Catherine Verret, René Bihannic, Romain Jouffroy, Benoit Frattini, Vivien Hong Tuan Ha, Pascal Dang-Minh, Stéphane Travers, Michel Bignand, Christophe Martinaud, Eliane Garrabe, Sylvain Ausset, Bertrand Prunet, Anne Sailliol, Jean Pierre Tourtier, PREHO-PLYO Study Group

Trials 2020 Jan 22;21(1):106 

Abstract

Background: Post-trauma bleeding induces an acute deficiency in clotting factors, which promotes bleeding and hemorrhagic shock. However, early plasma administration may reduce the severity of trauma-induced coagulopathy (TIC). Unlike fresh frozen plasma, which requires specific hospital logistics, French lyophilized plasma (FLYP) is storable at room temperature and compatible with all blood types, supporting its use in prehospital emergency care. We aim to test the hypothesis that by attenuating TIC, FLYP administered by prehospital emergency physicians would benefit the severely injured civilian patient at risk for hemorrhagic shock.

Methods/design: This multicenter randomized clinical trial will include adults severely injured and at risk for hemorrhagic shock, with a systolic blood pressure < 70 mmHg or a Shock Index >

1.1. Two parallel groups of 70 patients will receive either FLYP or normal saline in addition to usual treatment. The primary endpoint is the International Normalized Ratio (INR) at hospital admission. Secondary endpoints are transfusion requirement, length of stay in the intensive care unit, survival rate at day 30, usability and safety related to FLYP use, and other biological coagulation parameters.

Conclusion: With this trial, we aim to confirm the efficacy of FLYP in TIC and its safety in civilian prehospital care. The study results will contribute to optimizing guidelines for treating hemorrhagic shock in civilian settings.

Trial registration: ClinicalTrials.gov, NCT02736812. Registered on 13 April 2016. The trial protocol has been approved by the French ethics committee (CPP 3342) and the French Agency for the Safety of Medicines and Health Products (IDRCB 2015-A00866-43).

Impact of Prehospital Antibiotic Therapy on Septic Shock Mortality

Romain Jouffroy, Basile Gilbert, Jean Pierre Tourtier, Emmanuel Bloch-Laine, Patrick Ecollan, Vincent Bounes, Josiane Boularan, Teddy Léguillier, Papa Gueye-Ngalgou, Benoit Vivien

Prehosp Emerg Care 2020 May 15;1-8 

Background: Septic shock (SS) is associated with high morbidity and mortality rate. Early antibiotic therapy administration in septic patients was shown to reduce mortality but its impact on mortality in a prehospital setting is still under debate. To clarify this point, we performed a retrospective analysis on patients with septic shock who received antibiotics in a prehospital setting.

Methods: From April 15th, 2017 to March 1st, 2020, patients with septic shock requiring Mobile Intensive Care Unit (MICU) intervention were retrospectively analyzed to assess the impact of prehospital antibiotic therapy administration on a 30-day mortality.

Results: Three-hundred-eight patients with septic shock requiring MICU intervention in the prehospital setting were analyzed. The mean age of the study population was 70 ± 15 years. Presumed origin of SS was mainly pulmonary (44%), digestive (21%) or urinary (19%) infection. Overall 30-day mortality was 29%. Ninety-eight (32%) patients received antibiotic therapy. Using Cox regression analysis, we showed that prehospital antibiotic therapy significantly reduces 30- day mortality for patients with septic shock (hazard ratio = 0.56, 95%CI [0.35-0.89], p = 0.016).

Conclusion: In this retrospective study, prehospital antibiotic therapy reduces 30-day mortality of septic shock patients cared for by MICU. Further studies will be needed to confirm the beneficial effect of prehospital antibiotic therapy in association or not with prehospital hemodynamic optimization to improve the survival of septic shock patients.

Bomb Explosion: Ocular Effects of Primary, Secondary and Tertiary Mechanisms Mustafa Kalayci, Sadettin Er, Mehmet Tahtabasi

Clin Ophthalmol 2020 Apr 28;14:1145-1151 

Purpose: To report the type and severity of ocular injuries sustained by the survivors of a bomb-loaded explosion that occurred in Mogadishu, Somalia on December 28, 2019.

Patients and methods: The recorded data included age, gender, wounded eye, initial examination of ocular injuries and associated systemic injuries, initial visual acuity, anterior and posterior segment examinations. The type of injury (open vs closed globe), the injured zone of the globe, and the presence of a relative afferent pupil defect were evaluated in all cases where possible.

Results: After the explosion, ocular injuries were detected in 28 of 114 patients in our hospital. Thirty-two eyes of 28 patients were included in the study. The mean age was 32.4±6.7 years. The number of open-globe injuries was more than that of closed-globe injuries (26 vs 6; 81.25% vs 18.75%, respectively). Zone 1 was the most affected zone in open-globe injuries (18/26 eyes, 61.6%), followed by Zone 3 in six (23%) patients and Zone 2 in four (15.4%) patients. Sixteen open-globe injuries were laceration type (61.5%) and 10 (38.5%) were rupture type. An intraocular foreign body was detected in eight (30.8%) eyes with open-globe injuries. A total of 28 patients had 11 (39.3%) isolated eye injuries, whereas 17 (60.7%) had concomitant systemic injuries.

Conclusion: The frequency of blast-related ocular injuries is increasing. Today, the increase in the use of vehicle-borne improvised explosives in terrorist-related explosions leads to more frequent and serious ocular injuries.

Critical Care Transport Time Differences Between Ground, Helicopter VFR, and Helicopter IFR Transports

Tovy H Kamine, Leah Thomas, Collin Davis, Jason Cohen Aerosp Med Hum Perform 2020 Feb 1;91(2):98-101 

Abstract

BACKGROUND: In helicopter critical care and emergency medical services (HEMS) transportation, organizations aim for efficiency of the dispatch process. Most HEMS organizations do not provide transport under instrument flight rules (IFR), due to equipment and training cost. Boston MedFlight (BMF) provides IFR HEMS transport. We set out to determine if response time of IFR transport was superior to ground transport.

METHODS: A retrospective analysis of quality improvement data was performed. Data was collected by two observers sitting in the BMF control room in varying shifts. A process map of the dispatch process, from the dispatch call to the vehicle en route was developed. Critical points in the dispatch process were determined and a variety of time differences to determine the length of processes in the dispatch calculated. We compared median time differences between visual flight rules (VFR) flight and IFR flight, between IFR flight and ground transport, and between VFR and Ground for these points using a Mann-Whitney U-test.

RESULTS: During the study collection period, 443 transports occurred, of which 109 transports happened while the observers were present: 37 ground, 57 VFR, and 15 IFR. Due to weather, six IFR transports were declined. The overall time from dispatch call to vehicle en route was significantly increased for IFR flights [median: 30 min:8 s (interquartile range 19:06-49:04)] over both VFR flights [11:36 (9:24-17:06); P vs. IFR: 0.001] and ground transports [9:39 (6:59-14.51); P vs. IFR: 0.001]. Most of this increase was accounted for by increases in the time from dispatch to crew acceptance, and from rotor start to vehicle en route.

DISCUSSION: IFR conditions resulted in significantly increased dispatch times over both VFR flight and ground transport. The increase is likely a result of weather check, filing an IFR flight plan, and IFR release. Dispatch algorithms should be adjusted for this time delay of IFR transports.

Predictors of inhalation burn injury using fire site information

T Kaneko, H Tanaka, S Yamada, M Kitada, T Sakurai, M Harada, F Kimura, T Takahashi, S Kasaoka

Ann Burns Fire Disasters 2017 Dec 31;30(4):275-277 

Abstract

Inhalation burn injury (IBI) is a risk factor for mortality in burn patients. However, it is difficult to diagnose IBI using traditional physical examination alone, especially in prehospital settings.

Therefore, facial burn patients are usually treated for suspected IBI. In the present study, we investigated whether fire site information could predict IBI as an alternative to traditional physical examination. This retrospective single-centre analysis involved 27 facial burn patients with suspected IBI who were admitted between 2014 and 2016. The patients were divided into two groups (IBI and non-IBI) according to bronchoscopy findings. Fire site information was compared between the two groups. The IBI (n = 13) and non-IBI (n = 14) groups were compared. Domestic fire was more frequent in the IBI group (69% vs. 29%, P = 0.035). The IBI group included one patient with carboxyhemoglobin ≥10% on admission. Prehospitalization fire site information, particularly domestic fires, might predict IBI in facial burn patients.

Management of multiple traumas in emergency medicine department: A review

Parvin Kashani, Amin Saberinia

J Family Med Prim Care 2019 Dec 10;8(12):3789-3797 

Abstract

One of the main causes of adults' disability during their working age is multiple trauma. The process of medical care of patients who are injured seriously is still a challenging job. The primary treatment of these patients in the emergency medicine departments is the most required choice after the wilderness first aid and also would be very required before definitive care in the hospital. The main aim of emergency medicine departments is quick recognition and treatment of injuries which pose severe threat to patients' life in appropriate order of priority. The procedure of primary evaluation in emergency medicine department with the help of medical routine examination and ultrasonography is based on the concept of focused assessment with sonography in trauma (FAST) for identifying spontaneous intraperitoneal hemorrhage.

Emergency patients who suffer from massive hematothorax, serious lung and heart traumas, and penetrating traumas to the chest would undergo thoracotomy and patients who have few symptoms of perforated hollow viscous will undergo emergency laparotomy. Based on the trauma severity, emergency treatment could be the way to fast recovery of the structure of injured organ and its function. The subsequent goal, in the acute phase, will concentrate on preventing and stopping bleeding and secondary injuries like painful compartment syndrome or intra-abdominal infections (IAIs). However, the main aim of emergency medicine department in taking care of severely injured patients is the management of airway, protecting circulation and breathing, identification of neurologic problems, and whole body clinical examination with the help of healthcare providers.

Cricothyroidotomy needle length is associated with posterior tracheal wall injury: A randomized crossover simulation study (CONSORT)

Atsuko Katayama, Kunitaro Watanabe, Joho Tokumine, Alan Kawarai Lefor, Harumasa Nakazawa, Ippei Jimbo, Tomoko Yorozu

Medicine (Baltimore) 2020 Feb;99(9):e19331 

Background: Cricothyroidotomy is the final strategy in the "cannot intubate, cannot oxygenate" scenario, but half of needle cricothyroidotomy attempts result in failure. The most frequent complication in needle cricothyroidotomy is posterior tracheal wall injury. We hypothesized that needle length is related to posterior wall injury and compared needle cricothyroidotomy with a commercial kit to a modified shorter needle to evaluate success and posterior wall injury rates.

Methods: The commercial kit has a needle stopper to prevent posterior wall injury, with a penetrating length of 25 mm. We made long stopper to shorten the length by 5 mm (net 20 mm penetrating length). Residents were recruited, received a lecture about cricothyroidotomy and practiced needle cricothyroidotomy using the commercial kit on a simulator. They then performed cricothyroidotomy using the commercial kit or the shorter needle on an ex-vivo porcine larynx covered with artificial skin. An intra-tracheal endoscope recorded the procedure. The video was evaluated for success/failure or posterior wall injury by independent evaluators. Larynxes with a distance from the outer surface to the inner lumen exceeding 13 mm were excluded. The distance in each larynx was measured by dissection after the study. Success and posterior wall injury rates were analyzed using Fisher exact test (P < .05 was statistically significant).

Results: Forty-seven residents participated in the study. Data for two residents were excluded. There was no statistically significant difference in success rate between the commercial kit (100%, 45/45) and the shorter needle (91%, 41/45, P = .12). Failure was defined if the needle tip did not reach the lumen in four trials. Cannulated but complicated by posterior wall injury occurred in 33% (15/45) with the commercial kit and 5% (2/43) with the shorter needle (P < .01).

Conclusion: During needle cricothyroidotomy, force is needed for the needle to penetrate the cricothyroid ligament. The advancing needle sometimes cannot be stopped after penetrating the cricothyroid ligament. These data suggest that needle length is associated with posterior wall injury.

Exploring Nonbattle Injury in the Deployed Military Environment Using the Department of Defense Trauma Registry

David S Kauvar, Jennifer Gurney

Mil Med 2020 Mar 7; Online ahead of print. 

Abstract 

Introduction: The impact of disease and nonbattle injury (DNBI) on casualty burden of military operations has historically been greater than that of battle-related injuries. The ratio of battle to DNBI casualties has changed as advances in equipment, hygiene, and infectious diseases have been made; however, during military operations in Iraq and Afghanistan, 30% of serious injuries treated or evacuated from the area of operations were secondary to NBI. Most DoD research and intervention efforts focus on battle injuries; NBI has received much less practical attention. We aimed to explore the potential utility of the largest Department of Defense casualty database in identifying potential intervention targets for preventing NBI events.

Materials and methods: Phase I was a comprehensive NBI literature review from historical and current military operations. Phase II was an IRB exempt initial examination of relevant data contained in the Department of Defense Trauma Registry (DoDTR). Phase I: A MEDLINE search using the terms "military", "injury", and "nonbattle/non battle" was performed, and articles containing useful data points to characterize the unique risks of the modern deployed military environment and identify potentially preventable NBI hazards in the modern deployed military environment were retrieved and reviewed in full-text. Phase II: This information was used to explore data within the DoDTR's and its ability to provide data to inform NBI prevention efforts in the following areas: most prevalent NBI causes, NBI location and timing related to operational tempo, characteristics of the population at risk for NBI.

Results: Phase I: Falls and motor vehicle crashes (MVCs) accounted for most of the serious NBI in Iraq and Afghanistan. No specific epidemiologic data was readily available to guide NBI prevention efforts. Phase II was limited to NBI and falls from Iraq and Afghanistan in the DoDTR. Only aggregate data were available with a total of 1829 falls and 1899 MVCs. Case fatality for falls was 1.1% and for MVCs 6.5%. The greatest frequency of NBI was in Iraq among

U.S. Army personnel, but comparison of rates is not possible without reliable denominators for individual variables. Annual NBI incidence seems proportional to overall level of personnel deployed to each theater, but without knowledge of the true denominator of total deployed personnel, it is impossible to conclude definitively. The annual number of falls was stable throughout the period of highest operational tempo in Iraq (2003-2011), although MVCs were more common earlier in the operation (2003-2005), likely corresponding to greater operational maneuver.

Conclusions: The deployed military environment is dangerous and NBI presents a primary prevention target for expeditionary operations. The DoDTR is a database of detailed injury and medical care information and lacks much of the data required to perform a comprehensive epidemiologic NBI analysis. Specific prevention recommendations cannot be made based solely on DoDTR data and integration with other DoD databases that assess operational and tactical data should be considered.

The Role of Exparel Plus Meloxicam for Postoperative Pain Management

Alan David Kaye, Matthew B Novitch, Sam F Carlson, Mitchell C Fuller, Shane W White, Alexander R Haroldson, Jennifer A Kaiser, Mohamed A Elkersh, Andrew J Brunk, George M Jeha, Elyse M Cornett

Curr Pain Headache Rep 2020 Jan 30;24(3):6 

Abstract

Purpose of review: Acute postoperative pain reduction is a major target against the opioid crisis. While opioids have traditionally been the mainstay for postoperative analgesia, current practice has focused on a multimodal approach to pain control, including ultrasound-guided blocks with longer acting local anesthetic agents.

Recent findings: Non-steroidal anti-inflammatory drugs (NSAIDs), such as meloxicam, are an important class of medications utilized to manage pain in the perioperative period. An additional treatment used in perioperative or postoperative pain relief is Exparel, a bupivacaine (sodium channel blocker) liposomal injectable suspension with a 3-4-day duration of action. The long- acting mechanism and formulation of Exparel consistently has demonstrated decreased opioid use and pain scores in patients undergoing many different surgical procedures. A concern is that pH negatively alters the efficacy of bupivacaine, as in cases of inflamed tissue and acidic fluid pH. For this reason, a combination medication with both meloxicam and bupivacaine has been developed, which normalizes pH and has anti-inflammatory and anti-pain conduction properties. Clinical studies demonstrate that this combination agent can be extremely beneficial in treating postoperative pain. This manuscript summarizes the newest developments with regard to liposomal bupivacaine and the non-steroidal meloxicam, their roles in effective treatment of postoperative pain, contraindications, special considerations of using these medications, and future considerations. HTX-011 pairs up a new extended-release formulation of the local anesthetic bupivacaine with meloxicam, a well-established non-steroidal anti- inflammatory drug (NSAID).

Effectiveness of the combat application tourniquet for arterial occlusion in young children

Joseph R Kelly, Matthew J Levy, Jose Reyes, Jennifer Anders

J Trauma Acute Care Surg 2020 May;88(5):644-647 

Abstract

Background: Tourniquet use for extremity hemorrhage has become a mainstay in adult trauma care in last 15 years. The efforts of the Stop the Bleed campaign have increased the distribution and use of tourniquets in civilian settings in response to mass shootings and as part of disaster preparedness. Little research or published experience exists regarding the use of tourniquets in the pediatric population. This study sought to determine the minimum patient age on which the combat application tourniquet (CAT) is able to control extremity hemorrhage.

Methods: A convenience sample of pediatric patients, ages 1 year to 8 years, scheduled for elective orthopedic surgery at an academic hospital, were eligible for enrollment. Subject age, weight, height, blood pressure, and arm and leg circumferences were obtained. Once under general anesthesia, the pulse of an upper and a lower limb were obtained by Doppler, a CAT was then placed at the most proximal practical location of the limb until the corresponding pulse was either no longer obtainable by Doppler or until the tourniquet was as tight as its design allows. The tourniquet was removed after 30 seconds of arterial occlusion.

Results: Thirteen children, ages 2 years to 7 years were enrolled. Weights ranged from 12.8 kg to 23.9 kg, with a mean of 16.7 kg. Leg circumferences were 24.5 cm to 34.5 cm, with a mean of 27.9 cm and arm circumferences were 13 cm to 24 cm, with a mean of 16.3 cm. Subject heights were 87 cm to 122 cm, with a mean of 103.4 cm. Twenty-four total extremities were tested, 11 arms and 13 legs. Arterial occlusion was obtained on 100% of limbs tested (95% confidence interval, 85.8-100%).

Conclusion: This study is similar to previous adult tourniquet efficacy studies in design, size and outcomes. It is the first to show successful arterial occlusion on preschool-aged children with a commercial tourniquet in a controlled setting. The results suggest that the CAT can be used in school-aged children with severe extremity hemorrhage with a high likelihood of success.

Level of evidence: Therapeutic, level II.

Should Albumin be Considered for Prehospital Resuscitation in Austere Environments? A Prospective Randomized Survival Study in Rabbits

Bijan S Kheirabadi, Nahir Miranda, Irasema B Terrazas, Amber N Voelker, Rodolfo de Guzman, Nathan A Wienandt, Ammon W Brown, Michael A Dubick

Shock 2020 Sep;54(3):358-367 

Background: The new guidelines for prehospital care of combat casualties in shock recommend administration of whole blood or blood components to increase blood pressure to a permissible hypotensive level (i.e., hypotensive resuscitation [HR]). We investigated if 2 h of HR using limited volumes of whole blood, plasma, or albumin would lead to full recovery and long- term survival of rabbits subjected to severe hemorrhagic shock (HS).

Methods: Following instrumentation, laparotomy was performed on IV-anesthetized spontaneously breathing New Zealand white rabbits (3.0 kg -3.5 kg). Next, ∼40% of rabbits' blood volume was removed producing HS (mean arterial pressure [MAP]∼20 mm Hg). Fifteen minutes later, rabbits were resuscitated with a limited volume (12.5 mL/kg) of rabbit whole blood (fresh whole blood [FWB]), rabbit fresh frozen plasma (FFP), or 5% human albumin (ALB) to a target pressure (MAP) of 60 mm Hg (n=8/grp) and monitored for 2 h. Liver bleeding time was measured at baseline and 10 min after HR. Subsequently, animals were fully resuscitated (blood + lactated Ringer [LR]), surgically repaired, and recovered for 8 days. An untreated group (n = 6) was also included.

Results: Following HS, lactate and base deficit levels were increased to 8.2 ± 1.6 and 12.9 ±

3.1 mM respectively with no difference among groups. A lower volume of FWB volume was required to reach the target MAP (P < 0.05 vs. ALB) but MAP declined during the HR period (P< 0.01 vs. ALB). FWB provided higher hematocrit and platelets but it did not reduce lactate level faster than other fluids. Beside higher fibrinogen, no differences were found in hemostatic or resuscitative effects of FFP versus ALB. Bleeding time was prolonged with ALB and FFP fluids but unchanged with FWB. Untreated rabbits died during shock or shortly after. All treated rabbits except one recovered and lived for 8 days with normal blood tests and similar tissue histology.

Conclusions: Two hours of HR using a limited volume of FWB, FFP, or ALB led to full recovery and long-term survival of rabbits subjected to HS. Apart from bleeding time, no clinically significant differences were found among the three fluids. Five percent human albumin solutions are isotonic, iso-oncotic, ready-to-use, stable, and compatible with all blood types and should be considered for prehospital resuscitation where blood products are not available or not accepted.

A Randomized Trial of Mentored vs Nonmentored Military Medics Compared in the Application of a Wound Clamp Without Prior Training: When to Shut Up and Just Watch!

Andrew W Kirkpatrick, Jessica L Mckee, Itamar Netzer, Ian A Mckee, Paul McBeth, Juan P Wachs, Chad G Ball, Elon Glassberg

Mil Med 2020 Jan 7;185(Suppl 1):67-72 

Abstract

Introduction: Hemorrhage control is a basic task required of first responders and typically requires technical interventions during stressful circumstances. Remote telementoring (RTM) utilizes information technology to guide inexperienced providers, but when this is useful remains undefined.

Methods: Military medics were randomized to mentoring or not from an experienced subject matter expert during the application of a wound clamp (WC) to a simulated bleed.

Inexperienced, nonmentored medics were given a 30-second safety briefing; mentored medics were not. Objective outcomes were time to task completion and success in arresting simulated bleeding.

Results: Thirty-three medics participated (16 mentored and 17 nonmentored). All (100%) successfully applies the WC to arrest the simulated hemorrhage. RTM significantly slowed hemorrhage control (P = 0.000) between the mentored (40.4 ± 12.0 seconds) and nonmentored (15.2 ± 10.3 seconds) groups. On posttask questionnaire, all medics subjectively rated the difficulty of the wound clamping as 1.7/10 (10 being extremely hard). Discussion: WC application appeared to be an easily acquired technique that was effective in controlling simulated extremity exsanguination, such that RTM while feasible did not improve outcomes.

Limitations were the lack of true stress and using simulation for the task. Future research should focus on determining when RTM is useful and when it is not required.

Colloid osmotic pressure of contemporary and novel transfusion products

Robert B Klanderman, Joachim J Bosboom, Herbert Korsten, Thomas Zeiler, Ruben E A Musson, Denise P Veelo, Bart F Geerts, Robin van Bruggen, Dirk de Korte, Alexander P J Vlaar

Vox Sang 2020 May 6; Online ahead of print 

Background and objectives: Colloid osmotic pressure (COP) is a principal determinant of intravascular fluid homeostasis and a pillar of fluid therapy and transfusion. Transfusion- associated circulatory overload (TACO) is a leading complication of transfusion, and COP could be responsible for recruiting additional fluid. Study objective was to measure COP of blood products as well as investigate the effects of product concentration and storage lesion on COP.

Materials and methods: Three units of each product were sampled longitudinally. COP was measured directly as well as the determinants thereof albumin and total protein. Conventional blood products, that is red blood cell (RBC), fresh-frozen plasma (FFP) and platelet concentrates (PLTs), were compared with their concentrated counterparts: volume-reduced RBCs, hyperconcentrated PLTs, and fully and partially reconstituted lyophilized plasma (prLP). Fresh and maximally stored products were measured to determine changes in protein and COP. We calculated potential volume load (PVL) to estimate volume recruited using albumin's water binding per product.

Results: Colloid osmotic pressure varies widely between conventional products (RBCs, 1·9; PLTs, 7·5; and FFP, 20·1 mmHg); however, all are hypooncotic compared with human plasma COP (25·4 mmHg). Storage lesion did not increase COP. Concentrating RBCs and PLTs did not increase COP; only prLP showed a supraphysiological COP of 47·3 mm Hg. The PVL of concentrated products was lower than conventional products.

Conclusion: Colloid osmotic pressure of conventional products was low. Therefore, third-space fluid recruitment is an unlikely mechanism in TACO. Concentrated products had a lower calculated fluid load and may prevent TACO. Finally, storage did not significantly increase oncotic pressure of blood products.

Wound patterns in survivors of modern firearm related civilian Mass Casualty Incidents

Chase Knickerbocker, Mario F Gomez, Jose Lozada, Jonathan Zadeh, Eugene Costantini, Ivan Puente

Am J Disaster Med 2019 Summer;14(3):175-180 

Background: Civilian mass shooting events (CMSE) are occurring with increased frequency. Unfortunately, our knowledge of how to respond to these events is largely based on military experience and medical examiner data. While this translational knowledge has improved our basic response to such events, it is critical that we have a better under-standing of the wound patterns observed and the resources utilized in civilian mass shootings. This will allow us to better prepare our systems for future events.

Methods: Patients from two consecutive CMSEs presented to the same level 1 trauma center in Fort Lauderdale, Florida. The patients received by this center were studied for their wound patterns as well as the care they received while in the hospital. This included wound patterns and severity, subspecialty interventions, and hospitalization requirements.

Results: Both events produced a total of 19 victims who were brought to the center as trauma activations. The events had a combined fatality rate of 55 percent. Fifty-five percent of patients also had at least one wound to an extrem-ity, two with major vascular injuries who had field tourniquets applied. Sixty-three percent required an orthopedic interven-tion and 32 percent required intensive care unit (ICU) admission, half of these with prolonged ventilator support.

Conclusions: Given the number of extremity wounds in these events, we should continue the efforts championed by the stop the bleed campaign. The variety and quantity of specialties involved in the care of these patients also highlights the importance of a multidisciplinary approach to preparation and implementation of care in mass shooting events.

Potential survivability of prehospital injury deaths in New Zealand: a cross-sectional study

Bridget Kool, Rebbecca Lilley, Gabrielle Davie, Brandon de Graaf, Pararangi Reid, Charles Branas, Ian Civil, Bridget Dicker, Shanthi N Ameratunga

Inj Prev 2020 May 23;injuryprev-2019-043408 

Introduction: Acknowledging a notable gap in available evidence, this study aimed to assess the survivability of prehospital injury deaths in New Zealand.

Methods: A cross-sectional review of prehospital injury death postmortems (PM) undertaken during 2009-2012. Deaths without physical injuries (eg, drownings, suffocations, poisonings), where there was an incomplete body, or insufficient information in the PM, were excluded.

Documented injuries were scored using the AIS and an ISS derived. Cases were classified as survivable (ISS <25), potentially survivable (ISS 25-49) and non-survivable (ISS >49).

Results: Of the 1796 cases able to be ISS scored, 11% (n=193) had injuries classified as survivable, 28% (n=501) potentially survivable and 61% (n=1102) non-survivable. There were significant differences in survivability by age (p=0.017) and intent (p<0.0001). No difference in survivability was observed by sex, ethnicity, day of week, seasonality or distance to advanced- level hospital care. 'Non-survivable' injuries occurred more commonly among those with multiple injuries, transport-related injuries and aged 15-29 year. The majority of 'survivable' cases were deceased when found. Among those alive when found, around half had received either emergency medical services (EMS) or bystander care. One in five survivable cases were classified as having delays in receiving care.

Discussion: In New Zealand, the majority of injured people who die before reaching hospital do so from non-survivable injuries. More than one third have either survivable or potentially survivable injuries, suggesting an increased need for appropriate bystander first aid, timeliness of EMS care and access to advanced-level hospital care.

Tracking DO2 with Compensatory Reserve During Whole Blood Resuscitation in Baboons

Natalie J Koons, Betty Nguyen, Mithun R Suresh, Carmen Hinojosa-Laborde, Victor A Convertino

Shock 2020 Mar;53(3):327-334 

Abstract

Hemorrhagic shock can be mitigated by timely and accurate resuscitation designed to restore adequate delivery of oxygen (DO2) by increasing cardiac output (CO). However, standard care of using systolic blood pressure (SBP) as a guide for resuscitation may be ineffective and can potentially be associated with increased morbidity. We have developed a novel vital sign called the compensatory reserve measurement (CRM) generated from analysis of arterial pulse waveform feature changes that has been validated in experimental and clinical models of hemorrhage. We tested the hypothesis that thresholds of DO2 could be accurately defined by CRM, a noninvasive clinical tool, while avoiding over-resuscitation during whole blood resuscitation following a 25% hemorrhage in nonhuman primates. To accomplish this, adult male baboons (n = 12) were exposed to a progressive controlled hemorrhage while sedated that resulted in an average (± SEM) maximal reduction of 508 ± 18 mL of their estimated circulating blood volume of 2,130 ± 60 mL based on body weight. CRM increased from 6 ± 0.01% at the end of hemorrhage to 70 ± 0.02% at the end of resuscitation. By linear regression, CRM values of 6% (end of hemorrhage), 30%, 60%, and 70% (end of resuscitation) corresponded to calculated DO2 values of 5.9 ± 0.34, 7.5 ± 0.87, 9.3 ± 0.76, and 11.6 ± 1.3 mL O2·kg·min during resuscitation. As such, return of CRM to ∼65% during resuscitation required only ∼400 mL to restore SBP to 128 ± 6 mmHg, whereas total blood volume replacement resulted in over-resuscitation as indicated by a SBP of 140 ± 7 mmHg compared with an average baseline value of 125 ± 5 mmHg. Consistent with our hypothesis, thresholds of calculated DO2 were associated with specific CRM values. A target resuscitation CRM value of∼65% minimized the requirement for whole blood while avoiding over-resuscitation. Furthermore, 0% CRM provided a noninvasive metric for determining critical DO2 at approximately 5.3 mL O2·kg·min.

Dealing With Burn Patients in War Zones

Antonios Koutras, Athanasios Syllaios, Ioannis Tsilikis, Georgios Kalinterakis, Prokopis- Andreas Zotos, Ifigeneia Zouliati, Adamantios Michalinos, Ioannis Karavokyros, Dimitrios Schizas, Emmanouil Pikoulis

Disaster Med Public Health Prep 2020 Jan 8;1-5 

Abstract

Objective: Treating burn patients in the battlefield is one of the biggest challenges that military doctors and medical personnel can face. Wound patterns have been changed over time due to the introduction of new weapons, and many different aspects play a major role in the management of those burns nowadays. There is a potential gap in care of burn patients in war zones.

Methods: A thorough literature search in PubMed, scientific journals, and Internet sites was conducted in regard to burn patients and trauma in war zones.

Results: It is crucial for military surgeons to be able to stabilize burn patients during wartime conflicts, especially those patients who suffer from extreme burn injuries, as specialized treatment should be given. Medical personnel should be aware of all medication types used, the ways to minimize the risk of bacterial infection, and the ways to keep the injured safe.

Conclusions: Injured civilians with burn trauma in the field of battle are deserving care, and special recognition should be given to the non-governmental organizations (NGOs) that strive to ease human suffering in war zones. Proper management of burn patients in war zones is crucial, and military medical staff and NGOs can play a key role in that purpose.

Managing and securing the bleeding upper airway: a narrative review Michael Seltz Kristensen, Barry McGuire

Can J Anaesth 2020 Jan;67(1):128-140 

Abstract

Failure to manage bleeding in the airway is an important cause of airway-related death. The purpose of this narrative review is to identify techniques and strategies that can be employed when severe bleeding in the upper airway may render traditional airway management (e.g., facemask ventilation, intubation via direct/video laryngoscopy, flexible bronchoscopy) impossible because of impeded vision. An extensive literature search was conducted of bibliographic databases, guidelines, and textbooks using search terms related to airway management and bleeding. We identified techniques that establish a definitive airway, even in cases of impeded visibility resulting from severe bleeding in the airway. These include flexible video-/optical- scope-guided intubation via a supraglottic airway device; cricothyroidotomy or tracheotomy; and retrograde-, blind nasal-, oral-digital-, light-, and ultrasound-guided intubation. We provide a structured approach to managing bleeding in the airway that accounts for the source of bleeding and the estimated risk of failure to intubate using direct laryngoscopy or to achieve a front-of-neck access for surgical airway rescue. In situations where these techniques are predicted to be successful, the recommended approach is to identify the cricothyroid membrane (in preparation for rescue cricothyroidotomy), followed by rapid sequence induction. In situations where traditional management of the airway is likely to fail, we recommend an awake approach with one of the aforementioned techniques.

The ABCs of Ocular Trauma: Adapting a Familiar Mnemonic for Rapid Eye Exam in the Pre-Ophthalmic Zone of Care (Need link) 

Christiaan F Kroesen, Matthew Snider, James Bailey, Adam Buchanan, James W Karesh, Frank La Piana, Erin Seefeldt, Jo Ann Egan, Robert A Mazzoli

Mil Med 2020 Jan 7;185(Suppl 1):448-453 

Abstract

Evaluation and management of eye trauma is daunting to many practitioners. For general medical emergencies, the familiar ABCs mnemonic serves to both recompose the provider as well as provide a logical order for evaluation and action. We recently adapted an ABCs mnemonic to provide non-ophthalmologists with a familiar method for systematically evaluating and managing eye trauma. A = ACUITY. Visual acuity is the most importance piece of information in eye trauma. B = BEST exam of BOTH eyes. Starting with acuity, examination proceeds from the front to the rear of the eye. Examine the uninjured eye first. C = CONTIGUOUS STRUCTURES and CONTACT LENSES. Examine structures contiguous to the apparent injury. Inspect for contact lens wear. D = DRUGS, DIAGNOSTIC IMAGING, and the DON'TS. Start antibiotics, antiemetics, and analgesics. Administer tetanus. Obtain computerized tomography if available. Do not attempt ocular ultrasound or magnetic resonance imaging. Do not apply pressure to the eye. Do not patch the eye or apply any medication. E = EYE SHIELD and EVACUATE. Shield and ship to ophthalmology. The mnemonic was adapted to reflect current Joint Trauma Services and Tactical Combat Casualty Care practice guidelines. We believe this familiar mnemonic will serve as a useful tool in allowing non-ophthalmologists to comfortably and safely evaluate an eye for trauma.

Ionised calcium levels in major trauma patients who received blood en route to a military medical treatment facility

Tony Kyle, Ian Greaves, Anthony Beynon, Vicky Whittaker, Mike Brewer, Jason Smith Emerg Med J 2018 Mar;35(3):176-179 

Abstract

Background: Hypocalcaemia is a common metabolic derangement in critically ill patients. Blood transfusion can also contribute to depleted calcium levels. The aims of this study were to identify the incidence of hypocalcaemia in military trauma patients receiving blood products en route to a deployed hospital facility and to determine if intravenous calcium, given during the prehospital phase, has an effect on admission calcium levels.

Methods: This was a retrospective review of patients transported by the UK Medical Emergency Response Team in Afghanistan between January 2010 and December 2014 who were treated with blood products in the prehospital setting. Total units of blood products administered, basic demographics, Injury Severity Score and trauma type were collected.

Ionised serum calcium levels on admission to hospital were compared between those who received blood products without prehospital intravenous calcium supplemental therapy (non- treatment) and patients who were treated with 10 mL of intravenous calcium chloride (10%) concurrently with blood products (treatment).

Results: The study included 297 patients; 237 did not receive calcium and 60 did. The incidence of hypocalcaemia in the non-treatment group was 70.0% (n=166) compared with 28.3% (n=17) in the treatment group. Serum calcium levels were significantly different between the groups (1.03 mmol/L vs 1.25 mmol/L, difference 0.22 mmol/L, 95% CI 0.15 to 0.27). In the non-treatment group, 26.6% (n=63) had calcium levels within the normal range compared with 41.7% (n=25) in those who received calcium. There was a dose response of calcium level to blood products with a significant decrease in calcium levels as the volume of blood products increased.

Conclusion: Trauma patients who received blood products were at high risk of hypocalcaemia. Aggressive management of these patients with intravenous calcium during transfusion may be required.

Analysis of Prehospital Administration of Blood Products to Pediatric Casualties in Iraq and Afghanistan

Ryann S Lauby, Sarah A Johnson, Matthew A Borgman, James Bynum, Guyon J Hill, Steven G Schauer 

Prehosp Emerg Care. 2020 Oct 9;1-5 

Background: Hemorrhage is one of the leading causes of preventable death in both military and civilian trauma. Implementation of items such as tourniquets and hemostatic dressings are helpful in controlling hemorrhage and increasing the survival rate of casualties when such injuries occur. Prehospital blood transfusions are used to treat patients with severe injuries where the standard methods of hemorrhage control are not an effective form of treatment. There is limited research and no widely accepted protocol on pediatric prehospital blood transfusions. 

Methods: We queried the Department of Defense Trauma Registry (DODTR) for all pediatric subjects admitted to U.S. and Coalition fixed-facility hospitals in Iraq and Afghanistan from January 2007 to January 2016. This is a secondary analysis of casualties that received blood products prehospital. 

Results: From January 2007 through January 2016 there were 3439 pediatric casualties within the registry. Within this group, 22 casualties that received one or more blood product prehospital were identified. Children in the 10-14 years age (40%) group made up the largest proportion, 86% were male, almost all were injured by explosive (63%) or firearm (27%), and 77% survived to hospital discharge. The most frequently administered blood product was packed red cells (n = 17). Of the 22, 15 underwent massive transfusion within the first 24 hours of admission. 

Conclusions: Prehospital administration of blood products occurred infrequently within this pediatric dataset, but those that received blood were critically injured with most receiving a massive transfusion. Given the frequency with which medical personnel are carrying blood products in the prehospital, combat setting, guidelines specific to pediatric administration would be beneficial.

Analgesic use in contemporary burn practice: Applications to burn mass casualty incident planning

Sahar T Leazer, Jennifer E Nyland, Sandra M Escolas, James K Aden, Catherine A Rauschendorfer, Leopoldo C Cancio, Kevin K Chung

Burns 2020 Feb;46(1):90-96 

Abstract

Background: Determining the amount of analgesics required will help burn centers improve their ability to plan for a burn mass casualty incident (BMCI). We sought to quantify the amount of analgesics needed in an inpatient burn population. We hoped that assessing the analgesic use in daily burn care practice will potentially help estimate opioid needs in a burn mass casualty incident (BMCI).

Methods: We included patients with burns covering equal to or less than 30% total body surface area (TBSA), admitted from spring 2013 to spring 2015. Patient records were reviewed for analgesics and adjuncts, pain scores, age and TBSA. The doses of the different opioids administered were converted into morphine equivalent doses (MED).

Results: We enrolled 141 acute burn survivors with a mean TBSA of 8.2±0.6%. The lowest daily average MED per person was 24.6±2.0mg MED, recorded on the day of injury. The daily average MED per person increased until it peaked at 52.5±5.6mg MED at day 8 post-burn.

Then, it declined to 24.6±3.4mg MED by day 14. Bivariate regression analysis of average MED by TBSA showed a significant positive correlation (p<0.001). The analysis of average MED by age showed a significant negative correlation (p<0001).

Conclusion: Our study quantified opioid requirements in an inpatient burn population and identified TBSA (positively) and age (negatively) as significant predictors.

Whole Blood is Superior to Component Transfusion for Injured Children: A Propensity Matched Analysis

Christine M Leeper, Mark H Yazer, Darrell J Triulzi, Matthew D Neal, Barbara A Gaines

Ann Surg. 2020 Oct;272(4):590-594 

Objective: To compare a propensity-matched cohort of injured children receiving conventional blood component transfusion to injured children receiving low-titer group O negative whole blood.

Summary of background data: Transfusion of whole blood in pediatric trauma patients is feasible and safe. Effectiveness has not been evaluated.

Methods: Injured children ≥1 years old can receive up to 40 mL/kg of cold-stored, uncrossmatched whole blood during initial hemostatic resuscitation. Whole blood recipients (2016-2019) were compared to a propensity-matched cohort who received at least 1 uncrossmatched red blood cell unit in the trauma bay (2013-2016). Cohorts were matched for age, hypotension, traumatic brain injury, injury mechanism, and need for emergent surgery. Outcomes included time to resolution of base deficit, product volumes transfused, and INR after resuscitation.

Results: Twenty-eight children who received whole blood were matched to 28 children who received components. The whole blood group had faster time to resolution of base deficit [median (IQR) 2 (1-2.5) hours vs 6 (2-24) hours, respectively; P < 0.001]. The post-transfusion INR was decreased in whole blood vs component cohort [median (IQR) 1.4 (1.3-1.5) vs 1.6 (1.4-2.2); P = 0.01]. Lower plasma volumes [median (IQR) = 5 (0-15) mL/kg vs 11 (5-35) mL/kg; P = 0.04] and lower platelet volumes [median (IQR) = 0 (0-2) vs 3 (0-8); P = 0.03] were administered to the whole blood group versus component group. Other clinical variables (in-hospital death, hospital length of stay, intensive care unit length of stay, and ventilator days) did not differ between groups.

Conclusions: Compared to component transfusion, whole blood transfusion results in faster resolution of shock, lower post-transfusion INR, and decreased component product transfusion. Larger cohorts are required to support these findings.

Determining optimal needle size for decompression of tension pneumothorax in children- a CT-based study

Georg Leonhard, Daniel Overhoff, Lucas Wessel, Tim Viergutz, Marcus Rudolph, Michael Schöler, Holger Haubenreisser, Tom Terboven

Scand J Trauma Resusc Emerg Med 2019 Oct 11;27(1):90 

Background: For neonates and children requiring decompression of tension pneumothorax, specific recommendations for the choice of needle type and size are missing. The aim of this retrospective study was to determine optimal length and diameter of needles for decompression of tension pneumothorax in paediatric patients.

Methods: Utilizing computed tomography, we determined optimal length and diameter of needles to enable successful decompression and at the same time minimize risk of injury to intrathoracic structures and the intercostal vessels and nerve. Preexisting computed tomography scans of the chest were reviewed in children aged 0, 5 and 10 years. Chest wall thickness and width of the intercostal space were measured at the 4th intercostal space at the anterior axillary line (AAL) on both sides of the thorax. In each age group, three needles different in bore and length were evaluated regarding sufficient length for decompression and risk of injury to intrathoracic organs and the intercostal vessels and nerve.

Results: 197 CT-scans were reviewed, of which 58 were excluded, resulting in a study population of 139 children and 278 measurements. Width of the intercostal space was small at 4th ICS AAL (0 years: 0.44 ± 0.13 cm; 5 years: 0.78 ± 0.22 cm; 10 years: 1.12 ± 0.36 cm). The ratio of decompression failure to risk of injury at 4th ICS AAL was most favourable for a 22G/2.5 cm catheter in infants (Decompression failure: right: 2%, left: 4%, Risk of injury: right: 14%, left: 24%), a 22G/2.5 cm or a 20G/3.2 cm catheter in 5-year-old children (20G/3.2 cm: Decompression failure: right: 2.1%, left: 0%, Risk of injury: right: 2.1%, left: 17%) and a 18G/4.5 cm needle in 10-year-old children (Decompression failure: right: 9.5%, left: 9.5%, Risk of injury: right: 7.1%, left: 11.9%).

Conclusions: In children aged 0, 5 and 10 years presenting with a tension pneumothorax, we recommend 22G/2.5 cm, 20G/3.2 cm and 18G/4.5 cm needles, respectively, for acute decompression.

Tips and tricks: Supraglottic airway device insertion using a tongue depressor

Hyunyoung Lim, Mi Ae Jeong

Eur J Anaesthesiol 2020 Feb;37(2):154-155 

Supraglottic airway devices (SADs) have been widely used in general anaesthesia or in difficult tracheal intubation states, but sometimes incomplete insertion still occurs. The authors would like to introduce an

easier method to insert SADs using the tongue depressor used for operations in the mouth. After induction of anaesthesia, press the patient’s forehead with the right hand to create neck extension. Then insert the tongue depressor along the tongue with the left hand and lift it upward and forward as in laryngoscope insertion. Then insert the SAD towards the hard palate with the right hand. At the point where resistance occurs during insertion, remove the tongue depressor while pushing the SAD a little more. It can be inserted smoothly.

Comparison of glottic visualisation through supraglottic airway device (SAD) using bronchoscope in the ramped versus supine 'sniffing air' position: A pilot feasibility study

Wan Yen Lim, Stephanie Fook-Chong, Patrick Wong 

Indian J Anaesth. 2020 Aug;64(8):681-687 

Background and aims: Airway management in obese patients is associated with increased risk of difficult airway and intubation. After failed intubation, supraglottic airway-guided flexible bronchoscopic intubation (SAGFBI) may be required. It is uncertain whether SAGFBI is best performed in the ramped versus conventional supine "sniffing air" position. We conducted a feasibility study to evaluate the logistics of positioning, compared glottic views, and evaluated SAGFBI success rates. 

Methods: We conducted a prospective, pilot study in patients with a body mass index (BMI) 30-40 kg/m2 undergoing elective operations requiring tracheal intubation. All patients were placed in a ramped position. After induction, a supraglottic airway device (SAD) was inserted. A flexible bronchoscope was inserted into the SAD and a photograph of the glottic view taken. The patient was repositioned to the supine position. A second photograph was taken. SAGFBI was performed. Images were randomised and assessed by two independent anesthetists. 

Results: Of 17 patients recruited, 15 patients were repositioned successfully. There were no differences in glottic views observed in the two positions. SAGFBI was successful in 92.9% of patients (median time 91.5 s). Haemodynamic changes were noted in 42.7% of patients which resolved spontaneously. 

Conclusion: Our pilot study was completed within 5 months, achieved low dropout rate and protocol feasibility was established. SAGFBI was successfully and safely performed in obese patients, with a median time of 91.5 s. The time taken for SAGFBI was similar to awake intubation using FBI and videolaryngoscopy. Our study provided preliminary data supporting future, larger-scale studies to evaluate glottic views in the ramped versus supine positions.

Challenges of Burn Mass Casualty Incidents in the Prehospital Setting: Lessons From the Formosa Fun Coast Park Color Party

Chien-Hao Lin, Chih-Hao Lin, Chih-Yi Tai, Yu-You Lin, Frank Fuh-Yuan Shih

Prehosp Emerg Care Jan-Feb 2019;23(1):44-48 

Abstract

Objective: A burn mass casualty incident (BMCI) involving 499 patients occurred at a "color party" in Taiwan in June 27, 2015. We implemented a study to identify critical challenges regarding the prehospital emergency care in BMCIs. Methods: A 3-stage, mixed methods study was conducted in 2016. First, a statistical analysis of prehospital management using the data retrieved from the Emergency Medical Management System of the Ministry of Health and Welfare, Taiwan was performed. This was followed by a face-to-face, open-ended interview with the emergency medical technicians and the staff of the emergency operations center who responded to the incident; and the transcription of the interview data into constructed themes. 

Results: Our study indicated that the signs of inhalation injury needed to be incorporated in the field triage protocol for BMCIs; the collaborative utilization of regional emergency medical services may improve the surge capacity in the field; and an "island-hopping" strategy for patient transportation may allow the healthcare systems to manage the surge of burn patients more efficiently. Conclusions: Current field triage protocols may be insufficient for burn patients and should be further investigated. The practices in field triage, transport capacity, and transfer strategy can be considered as a part of an efficient prehospital emergency response to BMCIs.

Mild TBI/Concussion Clinical Tools for Providers Used Within the Department of Defense and Defense Health Agency

Megan A Lindberg, Seth A Kiser, Elisabeth M Moy Martin 

Fed Pract. 2020 Sep;37(9):410-419 

Background: Military personnel are at greater risk for sustaining mild traumatic brain injury (mTBI), or concussion, whether they are in a combat or garrison setting. Consequently, mTBI is a major health concern for health practitioners to understand, in order to provide timely assessment and treatment to service members (SM) who are suspected to have mTBI. 

Observations: Providing early diagnosis and effective management of symptoms can optimize recovery and promote healthy outcomes. Understanding what resources and guidelines are available is important for those evaluating active duty SMs within the Military Health System. 

Conclusions: This article showcases clinical tools for screening, evaluating, and diagnosing concussion used within the US Department of Defense, and provides resources for practitioners to find these clinical tools online.

Characteristics and treatments of ocular blast injury in Tianjin explosion in China

Yuanyuan Liu, Kang Feng, Hao Jiang, Fuhua Hu, Jun Gao, Wanhong Zhang, Wenjing Zhang, Bo Huang, Rodrigo Brant, Cheng Zhang, Hua Yan

BMC Ophthalmol 2020 May 6;20(1):185 

Background: To document characteristics and treatments of ocular blast injury from a fire and explosion.

Method: Authors retrospectively evaluated 116 patients with 166 eye injuries from six hospitals. Terminology of ocular injury referred to Birmingham Eye Trauma Terminology, and best- corrected visual acuity (BCVA) was categorized with the ocular trauma score (OTS) grading system. Incidence, preoperational and follow-up BCVA, treatment of severe ocular blast injuries were surveyed.

Results: Oculoplastic injuries accounted for the majority of eye injuries, while globe injuries were presented in 52 eyes with median baseline OTS 70 ranging from 26 to 100. No endophthalmitis occurred. The mean timing of the first-stage operations was 9.4 ± 6.4 h after blast, while second-stage operations were performed on average 14.7 ± 0.9 days post blast. Final BCVA of 68.8% of eyes achieved 20/200 or better as followed, 7 open globe injuries had a BCVA of no light perception. Additionally, eyes presenting rupture, retinal detachment, vitreous hemorrhage, choroidal injury and initial BCVA less than 20/200 had worse final visual outcomes, while globe penetration was not associated with poor visual acuity.

Conclusion: Various ocular injuries were commonly in the casualties of blast, in which open- globe injuries have worst visual prognosis. OTS is a valid approach for evaluation of prognosis and optimizing the therapeutic strategies subsequently in the massive casualty. Intense rescue and careful examination, proper surgery should be performed correctly to rescue patients.

Implementation of a Prehospital Patella Dislocation Reduction Protocol

Spencer Lord, James Brodell, Heather Lenhardt, Michael Dailey, Jeremy Cushman Prehosp Emerg Care 2020 Jan 29;1-4 

Abstract

Introduction: Acute patella dislocations account for up to 3% of all knee injuries. Prehospital care of patella dislocation often includes knee immobilization and pain management, but in the wilderness environment patella reductions are often performed by basic life support providers. Given the potential benefits of early reduction, the perceived low risk of harm and precedent with which the procedure can be performed, patella reduction was added to the EMT scope of practice in New York State. Our objective is to characterize the mechanism of patella related injuries and describe the success rate and complications experienced with the addition of a prehospital patella reduction protocol.

Methods: This was a retrospective review of a voluntary, preexisting, quality assurance database of cases in which a patella reduction was attempted between October 1, 2016 and June 30, 2018.Results: 90 patients underwent an attempt at patella reduction at one of 52 EMS agencies during the study period. The most common mechanism was a sports-related injury.

Patella reduction was successful 83/90 (92.2%). Median pain score was reduced from 10 to 2. There were no reported complications.

Conclusion: While a convenience sample, our results provide preliminary evidence that patella reduction can be performed by EMS providers with infrequent complication and offers significant pain relief.

Early Predictors of Near-Shore Spinal Injuries Among Emergency Department Patients

Tucker Lurie, Emilie Berman, Soha Hassan, Matthew Jackson, Jamie Falcon, Daniel Najafali, David Cowall, Bradford Schwartz, Stephen R Thom, Quincy K Tran 

J Emerg Med. 2021 Jan;60(1):17-24 

Background: Spinal injuries (SIs) can pose a significant burden to patients and family; delayed surgical intervention, associated with interhospital transfer, results in worse outcomes. 

Objective: This study aimed to identify early patient-centered factors associated with risk for near-shore SIs to assist clinicians with expeditious medical decision-making. 

Methods: We performed a multicenter retrospective study of all adults transported from Ocean City, Maryland to two emergency departments (EDs) and one regional trauma center for evaluation of suspected SIs from 2006 to 2017. Outcomes were any SI and any spinal cord injury (SCI). Multivariable logistic regression was performed for association of environmental and clinical factors with outcomes. 

Results: We analyzed 278 records, 102 patients (37%) were diagnosed with any SI and 41 (15%) were diagnosed with SCIs. Compared with patients without SI, patients with SI were more likely to be older (48 vs. 39 years), male (90% vs. 70%), with pre-existing spinal condition (62% vs. 33%), and injury caused by diving (11% vs. 2%). Multivariable logistic regression showed age (odd ratio [OR] 1.07; 95% confidence interval [CI] 1.04-1.11), diving (OR 3.5; 95% CI 3-100+), and wave height (OR 4.5; 95% CI 1.35-15.2) were associated with any SI, and a chief complaint of extremity numbness or tingling (OR 5.73; 95% CI 1.2-27.9) was associated with SCI. 

Conclusions: We identified older age, diving, and higher wave height as risk factors for any SI and symptoms of numbness and tingling were associated with SCIs. Clinicians should consider expediting these patients' transfers to a trauma center with neurosurgical capability.

Comparison of Two Supraglottic Airway Devices: I-gel Airway and ProSeal Laryngeal Mask Airway Following Digital Insertion in Nonparalyzed Anesthetized Patients

Ankur Luthra, Rajeev Chauhan, Amit Jain, Ishwar Bhukal, Shalvi Mahajan, Indu Bala

Anesth Essays Res Oct-Dec 2019;13(4):669-675 

Abstract

Aims: The study is aimed to compare the efficacy of I-gel and ProSeal laryngeal mask airway (PLMA) in nonparalysed anesthetized individuals following manufacturer-recommended digital insertion.

In this prospective randomized observational study, 40 American Society of Anesthesiologists I and II patients, aged 18-65 years scheduled for elective surgical procedures were allocated either to PLMA group (Group P, n = 20) or the I-gel group (Group I, n = 20). Following digital insertion of PLMA or I-gel, the following parameters were compared: insertion time, ease of insertion, number of attempts, failed insertion, airway reaction during insertion, oropharyngeal leak (OPL) pressure, and gastric insufflation on auscultation. Fiberoptic view of both the channels of the airway devices and ease of insertion of 12 F Ryle's tube through gastric drain channel were graded. Postoperative complications were also noted.

Results: First attempt and overall insertion success were similar (PLMA, 85% and 100%; I-gel 80% and 100%, respectively). Mean (standard deviation) insertion times were similar (PLMA, 27.40 [11.51] s; I-gel 25.45 [9.03] s). Mean OPL pressure was 3.5 cm H2O higher with PLMA (P< 0.012). The passage of Ryle's tube was easier through I-gel than PLMA. Grade I glottic view (full view of the vocal cords) was visible in 17 (85%) patients who were managed with I-gel whereas only 9 (45%) patients had Grade I view in the PLMA group.

Conclusion: The time required for digital insertion of PLMA and I-gel in nonparalyzed anesthetized patients is similar but PLMA forms a better oropharyngeal seal. I-gel is better positioned over the laryngeal framework and esophagus. I-gel allows easier passage of Ryle's tube through its drain channel than PLMA. The incidence and severity of postoperative sore throat and hoarseness was higher with PLMA.

Improved Hemodynamic Recovery and 72-Hour Survival Following Low-Volume Resuscitation with a PEGylated Carboxyhemoglobin in a Rat Model of Severe Hemorrhagic Shock

Antoni Macko, Forest R Sheppard, William H Nugent, Abe Abuchowski, Bjorn K Song

Mil Med 2020 Aug 14;185(7-8):e1065-e1072 

Introduction: Hemorrhage is a leading cause of death from potentially survivable civilian and military trauma. As projected conflicts move from settings of tactical and logistical supremacy to hyper-dynamic tactical zones against peer and near-peer adversaries, protracted medical evacuation times are expected. Treatment at the point-of-injury is critical. Although crystalloids like Lactated Ringer's (LR) are ubiquitous, whole blood (WB) is the preferred resuscitation fluid following hemorrhage; however, logistical constraints limit the availability of WB in prehospital settings. Hemoglobin-based oxygen carriers (HBOCs) offer both hemodynamic support and oxygen-carrying capacity while avoiding logistical constraints of WB. We hypothesized that low- volume resuscitation of severe hemorrhagic shock with an HBOC (PEGylated carboxyhemoglobin, [PC]) would improve hemodynamic recovery and 72-hour survival; comparable to WB and superior to LR.

Materials and methods: A total of 21 anesthetized male Sprague-Dawley rats underwent severe hemorrhagic shock followed by randomly assigned low-volume resuscitation with LR, WB, or PC, and then recovered from anesthesia for up to 72-hour observation. Mean arterial pressure (MAP) was recorded continuously under anesthesia, and arterial blood gases were measured at baseline (BL), 60 minutes post-hemorrhage (HS1h), and 24 hours post- resuscitation (PR24h). Survival was presented on a Kaplan-Meier plot and significance determined with a log-rank test. Cardiovascular and blood gas data were assessed with one- way analysis of variance and post hoc analysis where appropriate.

Results: All measured cardiovascular and blood chemistry parameters were equivalent between groups at BL and HS1h. BL MAP values were 90 ± 3, 86 ± 1, and 89 ± 2 mmHg for LR, PC, and WB, respectively. Immediately following resuscitation, MAP values were 57 ± 4, 74 ± 5, and 62 ± 3 mmHg, with PC equivalent to WB and higher than LR (P < 0.05). WB and LR were both lower than BL (P < 0.0001), whereas PC was not (P = 0.13). The PC group's survival to 72 hours was 57%, which was not different from WB (43%) and higher than LR (14%; P < 0.05).

Conclusions: A single bolus infusion of PC produced superior survival and MAP response compared to LR, which is the standard fluid resuscitant carried by combat medics. PC was not different from WB in terms of survival and MAP, which is encouraging because its reduced logistical constraints make it viable for field deployment. These promising findings warrant further development and investigation of PC as a low-volume, early treatment for hemorrhagic shock in scenarios where blood products may not be available.

Prehospital critical care is associated with increased survival in adult trauma patients in Scotland

Alistair Maddock, Alasdair R Corfield, Michael J Donald, Richard M Lyon, Neil Sinclair, David Fitzpatrick, David Carr, Stephen Hearns

Emerg Med J 2020 Mar;37(3):141-145 

Abstract

Background: Scotland has three prehospital critical care teams (PHCCTs) providing enhanced care support to a usually paramedic-delivered ambulance service. The effect of the PHCCTs on patient survival following trauma in Scotland is not currently known nationally.

Methods: National registry-based retrospective cohort study using 2011-2016 data from the Scottish Trauma Audit Group. 30-day mortality was compared between groups after multivariate analysis to account for confounding variables.

Results: Our data set comprised 17 157 patients, with a mean age of 54.7 years and 8206 (57.5%) of male gender. 2877 patients in the registry were excluded due to incomplete data on their level of prehospital care, leaving an eligible group of 14 280. 13 504 injured adults who received care from ambulance clinicians (paramedics or technicians) were compared with 776 whose care included input from a PHCCT. The median Injury Severity Score (ISS) across all eligible patients was 9; 3076 patients (21.5%) met the ISS>15 criterion for major trauma.

Patients in the PHCCT cohort were statistically significantly (all p<0.01) more likely to be male; be transported to a prospective Major Trauma Centre; have suffered major trauma; have suffered a severe head injury; be transported by air and be intubated prior to arrival in hospital. Following multivariate analysis, the OR for 30-day mortality for patients seen by a PHCCT was 0.56 (95% CI 0.36 to 0.86, p=0.01).

Conclusion: Prehospital care provided by a physician-led critical care team was associated with an increased chance of survival at 30 days when compared with care provided by ambulance clinicians.

Advancing Prehospital Combat Casualty Evacuation: Patients Amenable to Aeromedical Evacuation via Unmanned Aerial Vehicles

Joseph K Maddry, Allyson A Arana, Alejandra G Mora, Crystal A Perez, Julie E Cutright, Braden M Kester, Patrick C Ng, Steven G Schauer, Vikhyat S Bebarta 

Mil Med. 2021 Feb 26;186(3-4):e366-e372 

Introduction: The U.S. military currently utilizes unmanned aerial vehicles (UAVs) for reconnaissance and attack missions; however, as combat environment technology advances, there is the increasing likelihood of UAV utilization in prehospital aeromedical evacuation. Although some combat casualties require life-saving interventions (LSIs) during medical evacuation, many do not. Our objective was to describe patients transported from the point of injury to the first level of care and characterize differences between patients who received LSIs en route and those who did not. 

Materials and methods: We conducted a retrospective review of the records of traumatically injured patients evacuated between January 2011 and March 2014. We compared patient characteristics, complications, and outcomes based on whether they had an LSI performed en route (LSI vs. No LSI). We also constructed logistic regression models to determine which characteristics predict uneventful flights (no en route LSI or complications). 

Results: We examined 1,267 patient records; 47% received an LSI en route. Most patients (72%) sustained a blast injury and injuries to the extremities and head. Over 78% experienced complications en route; the LSI group had higher rates of complications compared to the No LSI group. Logistic regression showed that having a blunt injury or the highest abbreviated injury scale (AIS) severity score in the head/neck region are significant predictors of having an uneventful flight. 

Conclusion: Approximately half of casualties evaluated in our study did not receive an LSI during transport and may have been transported safely by UAV. Having a blunt injury or the highest AIS severity score in the head/neck region significantly predicted an uneventful flight.

Influence of Time to Transport to a Higher Level Facility on the Clinical Outcomes of US Combat Casualties with TBI: A Multicenter 7-Year Study

Joseph K Maddry, Allyson A Arana, Crystal A Perez, Kimberly L Medellin, Joni A Paciocco, Alejandra G Mora, William G Holder, William T Davis, Paco S Herson, Vikhyat S Bebarta

Mil Med 2020 Feb 13;185(1-2):e138-e145

Introduction: Traumatic brain injury (TBI) is a leading cause of death and disability worldwide and is associated with mortality rates as high as 30%. Patients with TBI are at high risk for secondary injury and need to be transported to definitive care expeditiously. However, the physiologic effects of aeromedical evacuation are not well understood and may compound these risks. Combat TBI patients may benefit from delayed aeromedical evacuation. The goal of this study was to evaluate the impact of transport timing out of theater via Critical Care Air Transport Teams (CCATT) to a higher level facility on the clinical outcomes of combat casualties with TBI.

Materials and methods: We performed a retrospective review of patients with TBI who were evacuated out of theater by CCATT from January 2007 to May 2014. Data abstractors collected flight information, vital signs, procedures, in-flight assessments, and outcomes. Time to transport was defined as the time from injury to CCATT evacuation out of combat theater. We calculated descriptive statistics and constructed regression models to determine the association between time to transport and clinical outcomes. This study was approved by the U.S. Air Force 59th Medical Wing Institutional Review Board.

Results: We analyzed the records of 438 patients evacuated out of theater via CCATT and categorized them into three groups: patients who were transported in one day or less (n = 165), two days (n = 163), and three or more days (n = 110). We used logistic regression models to compare outcomes among patients who were evacuated in two days or three or more days to those who were transported within one day while adjusting for demographics, injury severity, and injury type. Patients who were evacuated in two days or three or more days had 50% lower odds of being discharged on a ventilator and were twice as likely to return to duty or be discharged home than those who were evacuated within one day. Additionally, patients transported in three or more days were 70% less likely to be ventilated at discharge with a GCS of 8 or lower and had 30% lower odds of mortality than those transported within one day.

Conclusions: In patients with moderate to severe TBI, a delay in aeromedical evacuation out of the combat theater was associated with improved mortality rates and a higher likelihood of discharge to home and return to duty dispositions. This study is correlational in nature and focused on CCATT transports from Role III to Role IV facilities; as such, care must be taken in interpreting our findings and future studies are needed to establish a causal link between delayed evacuation and improved discharge disposition. Our study suggests that delaying aeromedical evacuation of TBI patients when feasible may confer benefit.

Intubation during a medevac flight: safety and effect on total prehospital time in the helicopter emergency medical service system

Hiroki Maeyama, Hiromichi Naito, Francis X Guyette, Takashi Yorifuji, Yuki Banshotani, Daisaku Matsui, Tetsuya Yumoto, Atsunori Nakao, Makoto Kobayashi 

Scand J Trauma Resusc Emerg Med. 2020 Sep 7;28(1):89 

Introduction: The Helicopter Emergency Medical Service (HEMS) commonly intubates patients who require advanced airway support prior to takeoff. In-flight intubation (IFI) is avoided because it is considered difficult due to limited space, difficulty communicating, and vibration in flight. However, IFI may shorten the total prehospital time. We tested whether IFI can be performed safely by the HEMS. 

Methods: We conducted a retrospective cohort study in adult patients transported from 2010 to 2017 who received prehospital, non-emergent intubation from a single HEMS. We divided the cohort in two groups, patients intubated during flight (flight group, FG) and patients intubated before takeoff (ground group, GG). The primary outcome was the proportion of successful intubations. Secondary outcomes included total prehospital time and the incidence of complications. 

Results: We analyzed 376 patients transported during the study period, 192 patients in the FG and 184 patients in the GG. The intubation success rate did not differ between the two groups (FG 189/192 [98.4%] vs. GG 179/184 [97.3%], p = 0.50). There were also no differences in hypoxia (FG 4/117 [3.4%] vs. GG 4/95 [4.2%], p = 1.00) or hypotension (FG 6/117 [5.1%] vs. GG 5/95 [5.3%], p = 1.00) between the two groups. Scene time and total prehospital time were shorter in the FG (scene time 7 min vs. 14 min, p < 0.001; total prehospital time 33.5 min vs. 40.0 min, p < 0.001). 

Conclusions: IFI was safely performed with high success rates, similar to intubation on the ground, without increasing the risk of hypoxia or hypotension. IFI by experienced providers shortened transportation time, which may improve patient outcomes.

Effectiveness and safety of small-bore tube thoracostomy (≤20 Fr) for chest trauma patients: A retrospective observational study

Toshinori Maezawa, Machi Yanai, Ji Young Huh, Koichi Ariyoshi 

Am J Emerg Med. 2020 Dec;38(12):2658-2660 

Introduction: Tube thoracostomy is an important treatment for traumatic hemothorax and pneumothorax. The optimal tube diameter remains unclear. To reduce invasiveness, we use small-bore chest tubes (≤20 Fr) for all trauma patients for whom tube thoracostomy is indicated in our emergency department (ED). The aim of this study was to investigate the effectiveness and safety of small-bore tube thoracostomy for traumatic hemothorax or pneumothorax. 

Method: We conducted a retrospective observational study at a single emergency medical center. This study included adult patients (≥18 years old) who had undergone tube thoracostomy for chest trauma in the ED during the 5 years from October 2013 to September 2018. We used 20 Fr chest tubes or 8 Fr pigtail catheters. The examined outcome was tube-related complications, such as tube obstruction, retained hemothorax, and unresolved pneumothorax. 

Results: A total of 107 tube thoracostomies were performed in 102 patients. The mean Injury Severity Score of these patients was 17.8 (±9.6), and the mean duration of the tube placement period was 3.9 days (±1.8). Eight patients developed tube-related complications (7.8%) (retained hemothorax: 4 patients (3.9%), unresolved pneumothorax: 4 patients (3.9%)). None of these cases were caused by tube obstruction. Although the drainage itself was effective, they underwent definitive invasive interventions to stop bleeding or air leak. 

Conclusion: Our study showed that the use of small-bore (≤20 Fr) chest tubes to treat traumatic hemothorax/pneumothorax achieved the purposes of tube thoracostomy. It might be possible to safely manage chest trauma with small-bore chest tubes.

Effect of tranexamic acid on intracranial haemorrhage and infarction in patients with traumatic brain injury: a pre-planned substudy in a sample of CRASH-3 trial patients

Abda Mahmood, Kelly Needham, Haleema Shakur-Still, Tim Harris, Sabariah Faizah Jamaluddin, David Davies, Antonio Belli, Fatahul Laham Mohamed, Caroline Leech, Hamzah Mohd Lotfi, Phil Moss, Fiona Lecky, Philip Hopkins, Darin Wong, Adrian Boyle, Mark Wilson, Melanie Darwent, Ian Roberts 

Emerg Med J. 2020 Dec 1;38(4):270-278 

Background: Early tranexamic acid (TXA) treatment reduces head injury deaths after traumatic brain injury (TBI). We used brain scans that were acquired as part of the routine clinical practice during the CRASH-3 trial (before unblinding) to examine the mechanism of action of TXA in TBI. Specifically, we explored the potential effects of TXA on intracranial haemorrhage and infarction. 

Methods: This is a prospective substudy nested within the CRASH-3 trial, a randomised placebo-controlled trial of TXA (loading dose 1 g over 10 min, then 1 g infusion over 8 hours) in patients with isolated head injury. CRASH-3 trial patients were recruited between July 2012 and January 2019. Participants in the current substudy were a subset of trial patients enrolled at 10 hospitals in the UK and 4 in Malaysia, who had at least one CT head scan performed as part of the routine clinical practice within 28 days of randomisation. The primary outcome was the volume of intraparenchymal haemorrhage (ie, contusion) measured on a CT scan done after randomisation. Secondary outcomes were progressive intracranial haemorrhage (post-randomisation CT shows >25% of volume seen on pre-randomisation CT), new intracranial haemorrhage (any haemorrhage seen on post-randomisation CT but not on pre-randomisation CT), cerebral infarction (any infarction seen on any type of brain scan done post-randomisation, excluding infarction seen pre-randomisation) and intracranial haemorrhage volume (intraparenchymal + intraventricular + subdural + epidural) in those who underwent neurosurgical haemorrhage evacuation. We planned to conduct sensitivity analyses excluding patients who were severely injured at baseline. Dichotomous outcomes were analysed using relative risks (RR) or hazard ratios (HR), and continuous outcomes using a linear mixed model. 

Results: 1767 patients were included in this substudy. One-third of the patients had a baseline GCS (Glasgow Coma Score) of 3 (n=579) and 24% had unilateral or bilateral unreactive pupils. 46% of patients were scanned pre-randomisation and post-randomisation (n=812/1767), 19% were scanned only pre-randomisation (n=341/1767) and 35% were scanned only post-randomisation (n=614/1767). In all patients, there was no evidence that TXA prevents intraparenchymal haemorrhage expansion (estimate=1.09, 95% CI 0.81 to 1.45) or intracranial haemorrhage expansion in patients who underwent neurosurgical haemorrhage evacuation (n=363) (estimate=0.79, 95% CI 0.57 to 1.11). In patients scanned pre-randomisation and post-randomisation (n=812), there was no evidence that TXA reduces progressive haemorrhage (adjusted RR=0.91, 95% CI 0.74 to 1.13) and new haemorrhage (adjusted RR=0.85, 95% CI 0.72 to 1.01). When patients with unreactive pupils at baseline were excluded, there was evidence that TXA prevents new haemorrhage (adjusted RR=0.80, 95% CI 0.66 to 0.98). In patients scanned post-randomisation (n=1431), there was no evidence of an increase in infarction with TXA (adjusted HR=1.28, 95% CI 0.93 to 1.76). A larger proportion of patients without (vs with) a post-randomisation scan died from head injury (38% vs 19%: RR=1.97, 95% CI 1.66 to 2.34, p<0.0001).

 

Conclusion: TXA may prevent new haemorrhage in patients with reactive pupils at baseline. This is consistent with the results of the CRASH-3 trial which found that TXA reduced head injury death in patients with at least one reactive pupil at baseline. However, the large number of patients without post-randomisation scans and the possibility that the availability of scan data depends on whether a patient received TXA, challenges the validity of inferences made using routinely collected scan data. This study highlights the limitations of using routinely collected scan data to examine the effects of TBI treatments.

Emerging hemorrhage control and resuscitation strategies in trauma: Endovascular to extracorporeal

James E Manning, Todd E Rasmussen, Samuel A Tisherman, Jeremy W Cannon

J Trauma Acute Care Surg 2020 Aug;89(2S Suppl 2):S50-S58 

This article reviews four emerging endovascular hemorrhage control and extracorporeal perfusion techniques for management of trauma patients with profound hemorrhagic shock including hemorrhage-induced traumatic cardiac arrest: resuscitative endovascular balloon occlusion of the aorta, selective aortic arch perfusion, extracorporeal life support, and emergency preservation and resuscitation. The preclinical and clinical studies underpinning each of these techniques are summarized. We also present an integrated conceptual framework for how these emerging technologies may be used in the future care of trauma patients in both resource-rich and austere environments.

Prehospital blunt traumatic arrest resuscitation augmented by whole blood: a case report

Julian G Mapp, Craig A Manifold, Alberto M Garcia, Jason L Aguilar, Michael L Stringfellow, Christopher J Winckler

Transfusion 2020 May;60(5):1104-1107 

Abstract

Background: Prehospital hemorrhagic shock accounts for approximately 25,000 civilian deaths annually in the United States. A balanced, blood-based resuscitation strategy is hypothesized to be the optimal treatment for these patients. Due to logistical constraints, delivering a balanced, blood-based resuscitation is difficult in the prehospital setting. A low titer O+ whole blood (LTO+ WB) ground ambulance initiative, may help alleviate this capability gap.

Case report: A 37-year-old female was involved in a motor vehicle collision at approximately 16:30. While she was trapped inside the vehicle, her mental status deteriorated. The patient was successfully extricated at 17:04 and found to be in cardiac arrest. The paramedics and firefighters quickly secured her airway and applied a mechanical CPR device. The first responder team obtained return of spontaneous circulation, but the patient's blood pressure was 43/27 mmHg. The paramedics transfused one unit of LTO+ WB. Twenty-one minutes after the initial LTO+ WB transfusion, the air ambulance team transfused a second unit of LTO+ WB. Upon hospital arrival, the transfusion was completed, and the patient's shock index improved to 1.0. The trauma team identified a grade 5 splenic injury with active extravasation. Interventional radiology performed an angiogram and successfully embolized the tertiary branches of the inferior splenic pole. She was extubated on postinjury Day one and discharged to her home neurologically intact on postinjury Day 12.

Conclusion: The prehospital availability of LTO+ WB may enhance the resuscitation of critically ill trauma patients.

Validation of Shock Index Pediatric-Adjusted (SIPA) for Children Injured in Warzones

Christopher W Marenco, Woo S Do, Daniel T Lammers, John D Horton, Kenneth Azarow, Matthew J Eckert

J Trauma Acute Care Surg 2020 Mar 12; Online ahead of print. 

Background: Shock Index Pediatric-Adjusted (SIPA) has been used to predict injury severity and outcomes after civilian pediatric trauma. We hypothesize that SIPA can predict the need for blood transfusion and emergent surgery among pediatric patients injured in warzones, where resources are limited and accurate triage is essential.

Methods: Retrospective review of the DoD Trauma Registry for all patients ≤17years, from 2008-2015. SIPA was determined using vital signs recorded upon arrival to the initial level of care. Patients were classified into two groups (normal v. elevated SIPA) using age-specific threshold values. Need for blood product transfusion (BPT) within 24 hours and emergent surgical procedures (ESP) was compared between groups. ICU admission, injury severity, and mortality were also compared. Regression analysis was performed to evaluate the relationship between SIPA and primary outcomes.

Results: 2121 patients were included with mean ISS 12±10. The mechanism of injury was penetrating (63%), blunt (25%), and burns (12%). Patients with an elevated SIPA (43%) had significantly greater need for BPT (49.2% v. 25.0%) and ESP (22.9% v. 16.0%), as well as mortality (10.3% v. 4.8%) and ICU admission (49.9% v. 36.1%), all p<0.001. Regression analysis confirmed an elevated SIPA as independently associated with both BPT (OR=2.36, 95% CI 1.19-2.94, p<0.001) and ESP (OR=1.29, 95% CI 1.01-1.64, p=0.044).

Conclusion: This is the first study of SIPA in pediatric warzone trauma. Elevated SIPA is associated with significantly increased need for blood product transfusion and emergent surgery, and may therefore serve as a valuable tool for planning and triage in austere settings.

Neurological outcome in patients after successful resuscitation in out-of-hospital settings

Martin Marinšek, Andreja Sinkovič, David Šuran

Bosn J Basic Med Sci 2020 Aug 3;20(3):389-395 

Neurological outcome is an important determinant of death in admitted survivors after out-of- hospital cardiac arrest (OHCA). Studies demonstrated several significant pre-hospital predictors of ischemic brain injury (time to resuscitation, time of resuscitation, and cause of OHCA). Our aim was to evaluate the relationship between post-resuscitation clinical parameters and neurological outcome in OHCA patients, when all recommended therapeutic strategies, including hypothermia, were on board. We retrospectively included consecutive 110 patients, admitted to the medical ICU after successful resuscitation due to OHCA. Neurological outcome was defined by cerebral performance category (CPC) scale I-V. CPC categories I-II defined good neurological outcome and CPC categories III-V severe ischemic brain injury. Therapeutic measures were aimed to achieve optimal circulation and oxygenation, early percutaneous coronary interventions (PCI) in acute coronary syndromes (ACS), and therapeutic hypothermia to improve survival and neurological outcome of OHCA patients. We observed good neurological outcome in 37.2% and severe ischemic brain injury in 62.7% of patients. Severe ischemic brain injury was associated significantly with known pre-hospital data (older age, cause of OHCA, and longer resuscitations), but also with increased admission lactate, in- hospital complications (involuntary muscular contractions/seizures, heart failure, cardiogenic shock, acute kidney injury, and mortality), and inotropic and vasopressor support. Good neurological outcome was associated with early PCI, dual antiplatelet therapy, and better survival. We conclude that in OHCA patients, post-resuscitation early PCI and dual antiplatelet therapy in ACS were significantly associated with good neurological outcome, but severe ischemic brain injury was associated with several in-hospital complications and the need for vasopressor and inotropic support.

Effectiveness and Usage Trends of Hemorrhage Control Interventions in Patients with Pelvic Fracture in Shock

Shokei Matsumoto, Tomohiro Funabiki, Kei Hayashida, Motoyasu Yamazaki, Takayuki Ebihara, Takashi Moriya

World J Surg 2020 Jul;44(7):2229-2236 

Background: Hemorrhage control for pelvic fractures remains challenging. There are several kinds of hemostatic interventions, including angiography/angioembolization (AG/AE), external fixation (EF), and resuscitative endovascular balloon occlusion of the aorta (REBOA). However, no large studies have been conducted for the comparative review of each intervention. In this study, we examined the usage trend of therapeutic interventions in Japan for patients with pelvic fractures in shock and the influence of these interventions on mortality.

Methods: Data of adult patients with pelvic fracture who were in shock were obtained from the Japanese Trauma Data Bank (2004-2014). The primary endpoint was the influence of each intervention (AG/AE, EF, and REBOA) on in-hospital mortality. We also investigated the frequency of each intervention.

Results: A total of 3149 patients met all our inclusion criteria. Specifically, 1131 (35.9%), 496 (15.8%), and 256 (8.1%) patients underwent AG, EF, and REBOA interventions, respectively. Therapeutic AE was performed in 690 patients who underwent AG (61.0%). The overall mortality rate was 31.4%. Multiple regression analysis identified that AG/AE (OR 0.64, 95% CI 0.52-0.80) and EF (OR 0.75, 95% CI 0.58-0.98) were significantly associated with survival, whereas REBOA (OR 4.17, 95% CI 3.00-5.82) was significantly associated with worse outcomes.

Conclusions: In Japan, patients with pelvic fracture who were in shock had high mortality rates. AG/AE and EF were associated with decreased mortality. AG may benefit from the early detection of arterial bleeding, leading to decreased mortality of patients with pelvic fracture in shock.

Organ ischemia during partial resuscitative endovascular balloon occlusion of the aorta: Dynamic 4D Computed tomography in swine

Yosuke Matsumura, Akiko Higashi, Yoshimitsu Izawa, Shuji Hishikawa, Hiroshi Kondo, Viktor Reva, Shigeto Oda, Junichi Matsumoto

Sci Rep 2020 Mar 30;10(1):5680 

Resuscitative endovascular balloon occlusion of the aorta (REBOA) increases proximal pressure, and simultaneously induces distal ischemia. We aimed to evaluate organ ischemia during partial REBOA (P-REBOA) with computed tomography (CT) perfusion in a swine model. The maximum balloon volume was recorded as total REBOA when the distal pulse pressure ceased. The animals (n = 4) were scanned at each 20% of the maximum balloon volume, and time-density curve (TDC) were analysed at the aorta, portal vein (PV), liver parenchyma, and superior mesenteric vein (SMV, indicating mesenteric perfusion). The area under the TDC (AUTDC), the time to peak (TTP), and four-dimensional volume-rendering images (4D-VR) were evaluated. The TDC of the both upper and lower aorta showed an increased peak and delayed TTP. The TDC of the PV, liver, and SMV showed a decreased peak and delayed TTP. The dynamic 4D-CT analysis suggested that organ perfusion changes according to balloon volume. The AUTDC at the PV, liver, and SMV decreased linearly with balloon inflation percentage to the maximum volume. 4D-VR demonstrated the delay of the washout in the aorta and retrograde flow at the inferior vena cava in the highly occluded status.

Mortality review of US Special Operations Command battle-injured fatalities

Edward L Mazuchowski, Russ S Kotwal, Jud C Janak, Jeffrey T Howard, Howard T Harcke, Harold R Montgomery, Frank K Butler, John B Holcomb, Brian J Eastridge, Jennifer M Gurney, Stacy A Shackelford

J Trauma Acute Care Surg 2020 May;88(5):686-695 

Abstract

Background: Comprehensive analyses of battle-injured fatalities, incorporating a multidisciplinary process with a standardized lexicon, is necessary to elucidate opportunities for improvement (OFIs) to increase survivability.

Methods: A mortality review was conducted on United States Special Operations Command battle-injured fatalities who died from September 11, 2001, to September 10, 2018. Fatalities were analyzed by demographics, operational posture, mechanism of injury, cause of death, mechanism of death (MOD), classification of death, and injury severity. Injury survivability was determined by a subject matter expert panel and compared with injury patterns among Department of Defense Trauma Registry survivors. Death preventability and OFI were determined for fatalities with potentially survivable or survivable (PS-S) injuries using tactical data and documented medical interventions.

Results: Of 369 United States Special Operations Command battle-injured fatalities (median age, 29 years; male, 98.6%), most were killed in action (89.4%) and more than half died from injuries sustained during mounted operations (52.3%). The cause of death was blast injury (45.0%), gunshot wound (39.8%), and multiple/blunt force injury (15.2%). The leading MOD was catastrophic tissue destruction (73.7%). Most fatalities sustained nonsurvivable injuries (74.3%). For fatalities with PS-S injuries, most had hemorrhage as a component of MOD (88.4%); however, the MOD was multifactorial in the majority of these fatalities (58.9%). Only 5.4% of all fatalities and 21.1% of fatalities with PS-S injuries had comparable injury patterns among survivors. Accounting for tactical situation, a minority of deaths were potentially preventable (5.7%) and a few preventable (1.1%). Time to surgery (93.7%) and prehospital blood transfusion (89.5%) were the leading OFI for PS-S fatalities. Most fatalities with PS-S injuries requiring blood (83.5%) also had an additional prehospital OFI.

Conclusion: Comprehensive mortality reviews of battlefield fatalities can identify OFI in combat casualty care and prevention. Standardized lexicon is essential for translation to civilian trauma systems.

Back to the Future: Whole Blood Resuscitation of the Severely Injured Trauma Patient

Christopher Cameron McCoy, Bryan A Cotton, Megan Brenner, Derek Roberts, Paula Ferrada, Tal Horer, David Kauvar, Mansoor Khan, Andrew Kirkpatrick, Carlos Ordonez, Bruno Perreira, Derek Roberts, Artai Priouzram, Juan Duchesne

Shock. 2020 Oct 28. doi: 10.1097/SHK.0000000000001685. Online ahead of print. 

Abstract 

Following advances in blood typing and storage, whole blood transfusion became available for the treatment of casualties during World War I. While substantially utilized during World War II and the Korean War, whole blood transfusion declined during the Vietnam War as civilian centers transitioned to blood component therapies. Little evidence supported this shift, and recent conflicts in Iraq and Afghanistan have renewed interest in military and civilian applications of whole blood transfusion. Within the past two decades, civilian trauma centers have begun to study transfusion protocols based upon cold-stored, low anti-A/B titer type O whole blood for the treatment of severely injured civilian trauma patients. Early data suggests equivalent or improved resuscitation and hemostatic markers with whole blood transfusion when compared to balanced blood component therapy. Additional studies are taking place to define the optimal way to utilize low-titer type O whole blood in both prehospital and trauma center resuscitation of bleeding patients.

Thoracic Injury in Patients Injured by Explosions on the Battlefield and in Terrorist Incidents

Andrew McDonald Johnston, Joseph Edward Alderman

Chest 2020 Apr;157(4):888-897 

Thoracic injury is common on the battlefield and in terrorist attacks, occurring in 10% to 70% of patients depending on the type of weapons used. Typical injuries seen include bullet, blast, and fragment injuries to the thorax, which are often associated with injuries to other parts of the body. Initial treatment prehospital and in the ED is carried out according to the principles of Tactical Combat Casualty Care or other standard trauma management systems. Immediately life-threatening problems including catastrophic hemorrhage are dealt with rapidly, and early consideration is given to CT scanning or rapid surgical intervention where appropriate. All patients should be given lung-protective ventilation. Treatment of these patients in the critical care unit is complicated by the severity of associated injuries and by features specific to combat trauma including blast lung injury, a high incidence of delirium, unusual infections such as colonization with multidrug-resistant Acinetobacter baumannii complex, and sometimes invasive fungal infections. A minority of patients with blast lung injury in published series have been successfully treated with prolonged respiratory support with high-frequency oscillatory ventilation and extracorporeal membrane oxygenation. The role of newer treatment options such as resuscitative endovascular balloon occlusion of the aorta is not yet known. In this article we review the relatively sparse literature on this group of patients and provide practical advice based on the literature and our institution's extensive experience of managing battlefield casualties.

Head-Neck Motion in Prehospital Trauma Patients under Spinal Motion Restriction: A Pilot Study

Neil McDonald, Dean Kriellaars, Erin Weldon, Rob Pryce

Prehosp Emerg Care 2020 Mar 18;1-8; Online ahead of print 

Abstract

Background: Spinal precautions are intended to limit motion of potentially unstable spinal segments. The efficacy of various treatment approaches for motion restriction in the cervical spine has been rigorously investigated using healthy volunteers and, to a lesser extent, cadaver samples. No previous studies have objectively measured this motion in trauma patients with potential spine injuries during prehospital care. Objective: The purpose of this study was to characterize head-neck (H-N) kinematics in a sample of trauma patients receiving spinal precautions in the field. Methods: This was a prospective observational study of trauma patients in the prehospital setting. Trauma patients meeting criteria for spinal precautions were eligible for inclusion. Participants received usual care, consisting of either a long backboard, cervical collar, and head blocks (BC) or a cervical collar only (CO), and behavior was categorized as compliant (C) or non-compliant (N). Three inertial measurement units (IMUs), placed on each participant's forehead, sternum, and stretcher, yielded data on H-N motion. Outcomes were described in terms of H-N displacement and acceleration, including single- and multi-planar values, root mean square (RMS), and bouts of continuous motion above pre-determined thresholds. Data were analyzed to compare H-N motion by phase of prehospital care, as well as treatment type and patient behavior.Results: Substantial single- and multi-plane H-N motion was observed among all participants. Maximum single-plane displacements were between 11.3± 3.0 degrees (rotation) and 19.0 ± 16.6 degrees (flexion-extension). Maximum multi-plane displacements averaged 31.2 ± 7.2 degrees (range: 7.2 to 82.1 degrees). Maximum multi-plane acceleration averaged 5.8 ± 1.4 m/s2 (range: 1.2 to 19.9 m/s2). There were no significant differences among participants between prehospital phase and treatment type. Non-compliant participants showed significantly more motion than compliant participants. Conclusion: Among actual patients, movement appears to be greater than previously recorded in simulation studies, and to be associated with patient behavior. Miniature IMUs are a feasible approach to field- based measurement of H-N kinematics in trauma patients. Future research should evaluate the effects of patient compliance, treatment, and phase of care using larger samples.

Feasibility of Prehospital Rapid Sequence Intubation in the Cabin of an AW169 Helicopter

Allan S McHenry, Leigh Curtis, E Ter Avest, Malcolm Q Russell, Amy V Halls, Sophie Mitchinson, Joanne E Griggs, Richard M Lyon, Air Ambulance Kent Surrey Sussex

 Air Med J. Nov-Dec 2020;39(6):468-472 

Objective: Prehospital rapid sequence intubation (RSI) is an important aspect of prehospital care for helicopter emergency medical services (HEMS). This study examines the feasibility of in-aircraft (aircraft on the ground) RSI in different simulated settings.

Methods: Using an AW169 aircraft cabin simulator at Air Ambulance Kent Surrey Sussex, 3 clinical scenarios were devised. All required RSI in a "can intubate, can ventilate" (easy variant) and a "can't intubate, can't ventilate" scenario (difficult variant). Doctor-paramedic HEMS teams were video recorded, and elapsed times for prespecified end points were analyzed. 

Results: Endotracheal intubation (ETI) was achieved fastest outside the simulator for the easy variant (median = 231 seconds, interquartile range = 28 seconds). Time to ETI was not significantly longer for in-aircraft RSI compared with RSI outside the aircraft, both in the easy (p = .14) and difficult variant (p = .50). Wearing helmets with noise distraction did not impact the time to intubation when compared with standard in-aircraft RSI, both in the easy (p = .28) and difficult variant (p = .24). 

Conclusion: In-aircraft, on-the-ground RSI had no significant impact on the time to successful completion of ETI. Future studies should prospectively examine in-cabin RSI and explore the possibilities of in-flight RSI in civilian HEMS services.

Syrian Civil War: a systematic review of trauma casualty epidemiology

Joshua McIntyre

BMJ Mil Health 2020 Aug;166(4):261-265 

Abstract

Background: The Syrian Civil War has caused over 400 000 traumatic deaths. Understanding the nature of war casualties is crucial to deliver healthcare improvement. Historic regional conflicts and Syrian mortality data have been characterised by blast injuries. The aim of this novel review is to assess the trauma epidemiology of Syrian Civil War casualties from the perspective of healthcare facilities.

Methods: This review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses method. Studies addressing Syria, trauma and war were investigated. Eligibility criteria included being conducted from a healthcare facility, published in English and peer reviewed. The outcomes were demography, mechanism of injury and anatomical injury site.

Results: 38 papers satisfied the eligibility criteria. 13 842 casualties were reported across the entire data set. Casualties were 88.8% male (n=4035 of 4544). Children contributed to 16.1% of cases (n=398 of 2469). Mortality rate was 8.6% (n=412 of 4774). Gunshot wound was the most common mechanism of injury representing 66.3% (n=7825 of 11799). Head injury was the most common injured site at 26.6% (n=719 of 2701).

Conclusions: This conflict has a distinct trauma profile compared with regional modern wars. The prevalence of gunshot wounds represents a marked change in mechanism of injury. This may be related to higher mortality rate and proportion of head injuries identified. This review cannot correlate mechanism of injury, demographics or injuries sustained to outcomes. The quality of data from the included studies lacked standardisation; future research and consistent reporting tools are required to enable further analysis.

Food and Drug Administration and Institutional Review Board Approval of a Novel Prehospital Informed Consent Process for Emergency Research

Jason McMullan, Christopher Droege, Col Richard Strilka, Christopher Lindsell, Michael J Linke

Prehosp Emerg Care. 2020 Sep 9;1-7. doi: 10.1080/10903127.2020.1806969. Online ahead of print. 

Abstract

Research on the management of acute pain in the prehospital setting is fraught with challenges. The prehospital setting is complex due to constrained time, resources, and training. Research activities must not interfere with the underlying clinical priorities of immediate patient stabilization and rapid transport to an appropriate hospital. The patient's pain, fear, and anxiety immediately after a traumatic event may interfere with undertaking an adequate informed consent process. Pain management trials do not satisfy the criteria for application of the U.S. Food and Drug Administration (FDA) 21 CFR 50.24 exception from informed consent. While nonstandard informed consent processes exist, waiver or alteration of informed consent may be limited if Institutional Review Boards or the FDA consider these studies to involve more than minimal risk related to the setting of the study, even if the interventions themselves might involve no more than minimal risk in other settings. In addition, any study requiring an Investigational New Drug application requires fully documented standard informed consent. Emergency Medical Services agencies and fire departments become research institutions, and paramedics become study staff, but both the institutions and the staff often lack experience conducting human subjects research and are rarely formally affiliated with the academic institution overseeing the research. As such, additional administrative burdens must be overcome in interventional prehospital studies, including additional training in the study protocol, research operations, and human subjects protections. Institutions conducting federally funded studies commit to regulations covering human subjects protections in the form of a Federalwide Assurance (FWA); prehospital organizations participating in research must either obtain an FWA or have coverage extended to them from an academic partner. We describe how these challenges were addressed during Institutional Review Board review and approval of an FDA-regulated randomized placebo-controlled trial of intranasal ketamine (vs. placebo) in acutely injured patients receiving standard of care fentanyl for prehospital pain management (NCT02866071). To our knowledge, this trial is the first instance in the United States of paramedics screening, consenting, enrolling, and administering study medications to patients without direct, real-time support from a dedicated clinical research team.

Intranasal Ketamine as an Adjunct to Fentanyl for the Prehospital Treatment of Acute Traumatic Pain: Design and Rationale of a Randomized Controlled Trial

Jason McMullan, Christopher Droege, Richard Strilka, Kimberly Hart, Christopher Lindsell

Prehosp Emerg Care. 2020 Oct 15;1-11. doi: 10.1080/10903127.2020.1808746. Online ahead of print. 

Objective: Acute pain management is fundamental in prehospital trauma care. Early pain control may decrease the risk of developing post-traumatic stress disorder (PTSD) and chronic pain. Fentanyl and ketamine are frequently used off-label, but there is a paucity of comparative data to guide decision-making about treatment of prehospital severe, acute pain. This trial will determine whether the addition of single dose of intranasal ketamine to fentanyl is more effective for the treatment of acute traumatic pain than administration of fentanyl alone.

Methods: This two-part study consists of prehospital and 90-day follow-up components (NCT02866071). The prehospital trial is a blinded, randomized, controlled trial of adult men (age 18-65 years) rating pain ≥7/10 after an acute traumatic injury of any type. Women will be excluded due to inability to confirm pregnancy status and unknown fetal risk. Paramedics will screen patients receiving standard of care fentanyl and, after obtaining standard informed consent, administer 50 mg intranasal ketamine or matching volume saline as placebo. Upon emergency department (ED) arrival, research associates will serially assess pain, concomitant treatments, and adverse side effects. Enrolled subjects will be approached for consent to participate in the 90-day follow-up study to determine rates of PTSD and chronic pain development. The primary outcome of the prehospital study is reduction in pain on the Verbal Numerical Rating Scale between baseline and 30-minutes after study drug administration. The proportion achieving a reduction of ≥2-points will be compared between study arms using a Chi-square test. Secondary outcomes of the prehospital trial include reduction in reported pain at the time of ED arrival and at 30 minutes intervals for up to three hours of ED care, the incidence of adverse events, and additional opiate requirements prior to ED arrival and within the first three hours of ED care. The outcomes in the follow-up study are satisfaction with life and development of PTSD or chronic pain at 90 days after injury. An intention-to-treat approach will be used.

Conclusion: These studies will test the hypotheses that ketamine plus fentanyl, when compared to fentanyl alone, effectively manages pain, decreases opiate requirements, and decreases PTSD at 90 days.

US Army Combat Medic Performance With Portable Ultrasound to Detect Sonographic Findings of Pneumothorax in a Cadaveric Model

Robert M Meadows, Jonathan D Monti, Mohamad A Umar, Kerri A Van Arnem, Eric J Chin, Christopher A Mitchell, Sue Love

J Spec Oper Med. Fall 2020;20(3):71-75 

Background: Ultrasound, due to recent advances in portability and versatility, has become a valuable clinical adjunct in austere, resource-limited settings and is well demonstrated to be an accurate/efficient means to detect pneumothorax. The purpose of this study was to evaluate the impact of hands-on ultrasound training on ultrasound-naive US Army combat medics' ability to detect sonographic findings of pneumothorax with portable ultrasound in a cadaver model.

Methods: Ultrasound-naive US Army combat medics assigned to conventional military units were recruited from a single US Army installation and randomized to receive either didactic training only, or "blended" (didactic and hands-on) training on ultrasound detection of pneumothorax. Blinded participants were asked to perform a thoracic ultrasound exam on ventilated human cadaver models. Primary outcome measured was sensitivity and specificity of detecting sonographic findings of pneumothorax between cohorts.

Results: Forty-three participants examined a total of 258 hemithoraces. The didactic-only cohort (n = 24) detected sonographic findings of pneumothorax with a sensitivity of 68% and specificity of 57%. The blended cohort (n = 19) detected sonographic findings of pneumothorax with an overall sensitivity of 91% and specificity of 80%. Detection sensitivities were similar between B-mode versus M-mode use.

Conclusion: US Army combat medics can use portable U/S to detect sonographic findings of pneumothorax in a human cadaver model with high sensitivity after a brief, blended (didactic and hands-on) training intervention.

Field-expedient thawing of fresh-frozen plasma

Michael Adam Meledeo, Grantham C Peltier, Colby S McIntosh, Jason B Corley, James A Bynum, Andrew P Cap

Transfusion 2020 Jun;60 Suppl 3:S87-S95 

Introduction: Frozen plasma is superior to crystalloids for hemorrhage resuscitation but remains logistically challenging in austere environments because of specialized clinical equipment for on-demand thawing. This research examines some ad hoc thawing techniques that have been implemented by military medical personnel.

Methods: Fresh-frozen plasma (FFP) units were thawed accordingly: using a slow cooker (three temperature settings) with preheated or room temperature water; affixing flameless ration heaters from meals ready-to-eat (MREs) to FFP and submerging in water; exposing FFP to electric kettle-boiled water; incubating with a sous vide immersion circulator; or using a clinical thawer (control). Hemostatic function, thrombin generation, factor activities, and essential chemistry were measured after thawing.

Results: Even at the highest temperatures, without preheated water the slow cooker doubled thawing time (62.5 min vs. control, 32.5 min; p < 0.0001), and the final temperature was 13.5°C versus 28.8°C in control (p < 0.01). When preheated, the slow cooker thawed in 31.3 minutes (p

< 0.05), with a final temperature of 22.4°C. Kettle-boiled water thawed in 23.0 minutes with a final temperature of 25.1°C. The sous vide thawed in 28.1 minutes, with a final temperature of 20.2°C. MRE heaters were insufficient. Functional measures were similar in all conditions.

Discussion: In emergencies, protracted plasma thawing is unacceptable, and slower thawing methods also produced cryoprecipitate. Although no functional changes were observed with boiled water thawing, potential negative physiological impacts must be examined. Safe, controlled thawing can be obtained with the sous vide, although optimization requires further testing.

Mass Casualty Shootings and Emergency Preparedness: A Multidisciplinary Approach for an Unpredictable Event

Patrick Melmer, Margo Carlin, Christine A Castater, Deepika Koganti, Stuart D Hurst, Brett M Tracy, April A Grant, Keneeshia Williams, Randi N Smith, Christopher J Dente, Jason D Sciarretta

J Multidiscip Healthc 2019 Dec 10;12:1013-1021 

Mass casualty events (MCE) are an infrequent occurrence to most daily healthcare systems however these incidents are the causation for new hospital preparedness and the development of coordinated emergency services. The broad support and operational plans outside the hospital include emergency medical services, local law enforcement, government agencies, and city officials. Modern-day hospital disaster preparedness goals include scheduled training for healthcare personnel to ensure effective and accurate triage for a high-volume of injured patients. This MDT collaboration strengthens the emergency response to optimize the delivery of life-saving care during MCEs. This review identifies the clinical importance of the interdisciplinary team interactions and the lessons learned from past MCE experiences, strengthening healthcare system readiness for such critical incidents.

BET 1: Does inhaled tranexamic acid reduce morbidity in adults with haemoptysis?

Jennifer Mervau, Seamon Jason, Jeffrey S Jones

Emerg Med J 2020 Jan;37(1):45-46 

Abstract

A short cut review was carried out to establish whether inhaled tranexamic acid is more effective than placebo at controlling bleeding in patients with haemoptysis. Thirty-four papers were found using the reported searches, of which one presented the best available evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of this paper is tabulated. It is concluded that in patients with non-massive haemoptysis, management with nebulised TXA leads to fast resolution.

Effect of tranexamic acid in traumatic brain injury: a case report

Toru Miike, Yuichiro Sakamoto, Satoshi Inoue

J Nippon Med Sch 2020 Apr 30;Online ahead of print. 

Traumatic brain injury (TBI) often results in coagulopathy, which increases mortality risk. The clinical randomization of an antifibrinolytic in significant head injury (CRASH) -2 and CRASH-3 trials confirmed that tranexamic acid (TXA) was effective after trauma. Herein, we report a unique coagulation change in a patient with TBI given TXA after point-of-care assessment.

Coagulation functions were impaired on admission. At 1 hour after TXA administration, clotting time was further prolonged in the extrinsic coagulation pathway but shortened in the intrinsic coagulation system. The results of a total thrombus-formation analysis system test showed improved blood clot formation ability. Intrinsic coagulation and clot formation improved after TXA administration in a TBI patient with coagulopathy.

Evaluation of pain management in medical transfer of trauma patients by air

Isabelle H Miles, Russell D MacDonald, Sean W Moore, James Ducharme, Christian Vaillancourt

CJEM 2019 Nov;21(6):776-783 

Abstract

Objectives: With regionalized trauma care, medical transport times can be prolonged, requiring paramedics to manage patient care and symptoms. Our objective was to evaluate pain management during air transport of trauma patients.

Methods: We conducted a 12-month review of electronic paramedic records from a provincial critical care transport agency. Patients were included if they were ≥18 years old and underwent air transport to a trauma centre, and excluded if they were Glasgow Coma Scale score <14, intubated, or accompanied by a physician or nurse. Demographics, injury description, and transportation parameters were recorded. Outcomes included pain assessment via 11-point numerical rating scale, patterns of analgesia administration, and analgesia-related adverse events. Results were reported as mean ± standard deviation, [range], (percentage).

Results: We included 372 patients: 47.0 years old; 262 males; 361 blunt injuries. Transport duration was 82.4 ± 46.3 minutes. In 232 (62.4%) patients who received analgesia, baseline numerical rating scale was 5.9 ± 2.5. Fentanyl was most commonly administered at 44.3 [25-60] mcg. Numerical rating scale after first analgesia dose decreased by 1.1 [-2-7]. Thereafter, 171 (73.7%) patients received 2.4 [1-18] additional doses. While 44 (23.4%) patients had no change in numerical rating scale after first analgesia dose, subsequent doses resulted in no change in numerical rating scale in over 65% of patients. There were 43 adverse events recorded, with nausea the most commonly reported (39.5%).

Conclusions: Initial and subsequent dose(s) of analgesic had minimal effect on pain as assessed via numerical rating scale, likely due in part to inadequate dosing. Future research is required to determine and address the barriers to proper analgesia.

The Light Role CCP: A Blueprint for Far Forward Medical Support to Contemporary Operations

John Miles, C Jones

BMJ Mil Health 2020 May 17;bmjmilitary-2020-001435 

November 2018 saw the deployment of a medical team with a remit to provide far forward medical support to UK, Coalition and indigenous forces. The delivery of this capability demanded a solution unique within the UK Defence Medical Services. The 'light role' casualty collection points provided emergency medical care to 475 casualties over a 4-month period. The success of the deployment was dependant on the ability to remain light and agile which brought with it logistical considerations. The clinical caseload was predominantly secondary blast injury and gunshot wound (GSW). The positioning of a Role 1 facility close to the front line of troops enabled early Damage Control Resuscitation including the delivery of blood products.

MEDEVAC to Role 2 was enabled by indigenous forces. The unique situation demanded bespoke solutions for documentation and blood warming. The lessons learnt during the deployment may form a blueprint for future contingency operations.

Consensus Recommendations on the Prehospital Care of the Injured Athlete With a Suspected Catastrophic Cervical Spine Injury

Brianna M Mills, Kelsey M Conrick, Scott Anderson, Julian Bailes, Barry P Boden, Darryl Conway, James Ellis, Francis Feld, Murphy Grant, Brian Hainline, Glenn Henry, Stanley A Herring, Wellington K Hsu, Alex Isakov, Tory Lindle, Lance McNamara, Jason P Mihalik, Timothy L Neal, Margot Putukian, Frederick P Rivara, Allen K Sills, Erik E Swartz, Monica S Vavilala, Ron Courson 

Clin J Sport Med. 2020 Jul;30(4):296-304 

Introduction: Sports participation is among the leading causes of catastrophic cervical spine injury (CSI) in the United States. Appropriate prehospital care for athletes with suspected CSIs should be available at all levels of sport. The goal of this project was to develop a set of best-practice recommendations appropriate for athletic trainers, emergency responders, sports medicine and emergency physicians, and others engaged in caring for athletes with suspected CSIs. 

Methods: A consensus-driven approach (RAND/UCLA method) in combination with a systematic review of the available literature was used to identify key research questions and develop conclusions and recommendations on the prehospital care of the spine-injured athlete. A diverse panel of experts, including members of the National Athletic Trainers' Association, the National Collegiate Athletic Association, and the Sports Institute at UW Medicine participated in 4 Delphi rounds and a 2-day nominal group technique (NGT) meeting. The systematic review involved 2 independent reviewers and 4 rounds of blinded review. 

Results: The Delphi process identified 8 key questions to be answered by the systematic review. The systematic review comprised 1544 studies, 49 of which were included in the final full-text review. Using the results of the systematic review as a shared evidence base, the NGT meeting created and refined conclusions and recommendations until consensus was achieved. 

Conclusions: These conclusions and recommendations represent a pragmatic approach, balancing expert experiences and the available scientific evidence.

Prehospital time and mortality in patients requiring a highest priority emergency medical response: a Danish registry-based cohort study

Elisabeth Helen Anna Mills, Kristian Aasbjerg MD, PhD, Steen Moeller Hansen, Kristian Bundgaard Ringgren MB, Michael Dahl MD, PhD, Bodil Steen Rasmussen, Christian Torp- Pedersen, Peter Søgaard, Kristian Kragholm

BMJ Open 2019 Nov 21;9(11):e023049 

Objective: To examine the association between time from emergency medical service vehicle dispatch to hospital arrival and 1-day and 30-day mortality.

Design: Register-based cohort study.

Setting: North Denmark Region (≈8000 km2, catchment population ≈600 000).

Participants: We included all highest priority dispatched ambulance transports in North Denmark Region in 2006-2012.

Interventions: Using logistic regression and the g-formula approach, we examined the association between time from emergency dispatch to hospital arrival and mortality for presumed heart, respiratory, cerebrovascular and other presumed medical conditions, as well as traffic or other accidents, as classified by emergency dispatch personnel.

Main outcome measures: 1-day and 30-day mortality.

Results: Among 93 167 individuals with highest priority ambulances dispatched, 1948 (2.1%) were dead before the ambulance arrived and 19 968 (21.4%) were transported to the hospital under highest priority (median total prehospital time from dispatch to hospital arrival 47 min (25%-75%: 35-60 min); 95th percentile 84 min). Among 18 709 with population data, 1-day mortality was 10.9% (n=2038), and was highest for patients with dyspnoea (20.4%) and lowest for patients with traffic accidents (2.8%). Thirty-day mortality was 18.3% and varied between 36.6% (patients with dyspnoea) and 3.7% (traffic accidents). One-day mortality was not associated with total prehospital time, except for presumed heart conditions, where longer prehospital time was associated with decreased mortality: adjusted OR for >60 min vs 0-30 min was 0.61 (95% CI 0.40 to 0.91). For patients with dyspnoea, OR for >60 min vs 0-30 min was 0.90 (95% CI 0.56 to 1.45), for presumed cerebrovascular conditions OR 1.41 (95% CI 0.53 to 3.78), for other presumed medical conditions OR 0.84 (95% CI 0.70 to 1.02), for traffic accidents OR 0.65 (95% CI 0.29 to 1.48) and for other accidents OR 0.84 (95% CI 0.47 to 1.51). Similar findings were found for 30-day mortality.

Conclusions: In this study, where time from emergency dispatch to hospital arrival mainly was <80 min, there was no overall relation between this prehospital time measure and mortality.

Characteristics of Open Globe Injuries in the United States From 2006 to 2014

Tahreem A Mir, Joseph K Canner, Sidra Zafar, Divya Srikumaran, David S Friedman, Fasika A Woreta

JAMA Ophthalmol 2020 Jan 23;138(3):268-275 

Abstract

Importance: Open globe injuries can lead to substantial visual morbidity and lifelong sequelae. Interventions to reduce the burden of open globe injuries in the United States require a better understanding of these injuries through well-designed epidemiologic investigations.

Objective: To examine the incidence, common injury mechanisms, and economic burden of open globe injuries in the United States.

Design, setting, and participants: This retrospective, cross-sectional study of US nationwide emergency department (ED) data assessed all ED visits of patients with a primary diagnosis of open globe injury in the Nationwide Emergency Department Sample (NEDS) from January 1, 2006, to December 31, 2014. Data analysis was performed from August 29, 2018, to November

11, 2019.

Main outcomes and measures: Annual incidence of open globe injuries by age, sex, mechanism of injury, and concomitant diagnosis, as well as median charges associated with open globe injuries and variables associated with hospitalization.

Results: A total of 124 989 ED visits for open globe injuries were assessed, with an incidence of 4.49 per 100 000 population in the United States from 2006 to 2014 (mean [SD] age of study participants, 37.7 [22.5] years; 94 078 [75.3%] male). The incidence was highest in 2006 (5.88 per 100 000 population) and decreased by 0.3% per month between 2006 and 2014 (incidence rate ratio, 0.99; 95% CI, 0.99-0.99; P < .001). Open globe injuries occurred in 37 060 individuals (30.6%) of low socioeconomic status. The most common injury mechanism was being struck by or against an object or person (40 119 of all 124 989 injury mechanisms [32.1%]). Open globe injuries associated with falls increased 6.6% between 2006-2010 and 2011-2015 (95% CI, 1.04- 1.08; P < .001) and were the most common injury mechanism in individuals older than 70 years. The total cost associated with open globe injuries was $793 million. The cost of ED visits increased from $865 during 2006-2010 to $1557 during 2011-2015. Inpatient costs similarly increased from $21 527 during 2006-2010 to $30 243 during 2011-2015.

Conclusions and relevance: The incidence of open globe injuries in the United States decreased from 2006 to 2014. Although the data are from 5 to 13 years ago, these findings appear to provide valuable information for targeting preventive measures toward individuals at highest risk; targeting young men with lower socioeconomic status and individuals 70 years or older at an increased risk of falls may help lower the incidence of open globe injuries.

Comparison of Fiberoptic-Guided Tracheal Intubation Through Intubating Laryngeal Mask Airway (ILMA) FastrachTM and Ambu® Aura-i™: A Randomized Clinical Study

 Navya Mishra, Avnish Bharadwaj 

Cureus. 2020 Sep 1;12(9):e10178 

Abstract 

Background and aim The primary aim of the study was to compare the intubation characteristics and effectiveness of intubating laryngeal mask airway (ILMA) and Ambu® Aura-i™ as a conduit for facilitating fiberoptic-guided intubation. Methods Eighty patients were enrolled in the randomized-controlled hospital-based study. After inducing general anesthesia, an appropriately sized ILMA (group 1)/Ambu Aura-I (group 2) was placed. Fiberoptic assessment of the glottic view was done followed by fiberoptic-guided tracheal intubation. The time taken for the insertion of ILMA/Ambu Aura-i, glottic view grading, time taken for fiberoptic-guided intubation, ease of intubation, time taken for the removal of ILMA/Ambu Aura-i were recorded. Data analysis was done using the two-tailed independent t-test, paired t-test, and Fisher's exact probability test. Result Anthropometric and airway parameters were similar in both groups. The success rate of the insertion of both devices was 100%. In group 1, the mean time taken for the insertion was 20.53±1.91, and it was 13.98±2.4 in group 2 (P<0.001S). Fiberoptic assessment of the glottic view in group 1 (ILMA group) was grade 1 in 80% of the patients, whereas it was 92% in group 2 (Ambu Aura-i) (P=0.54). The mean time taken for fiberoptic-guided intubation was 14.95±1.85 in group 1 and 14.15±1.37 in group 2 (P>0.001). No significant difference was observed according to the number of attempts in intubating through ILMA/Ambu Aura-i. Seventy-five percent (75%) in group 1 and 87.5% in group 2 were successfully inserted on the first attempt (𝑝 = 0.33). The time taken for the removal of the device was 11.87 +1.265 seconds in group 1 and 11.25±1.58 seconds in group 2 (P=0.054). Conclusion The Ambu Aura-i scores superiorly over ILMA in requiring less time for successful insertion on the basis of statistical analysis and hence appears to be a better independent ventilatory device.

A Case Series of Air Force Pararescue Long-Range Ocean Rescues

Jesse W Mix, Erik Scott DeSoucy, Alex Hilser, Daniel J Houser, Kubwimana M Mhayamaguru, John Dorsch, Joshua B Gaither, Stephen C Rush 

J Spec Oper Med. Fall 2020;20(3):122-127. 

Background: US Air Force (USAF) pararescuemen (PJs) perform long-range ocean rescue missions for ill or injured civilians when advanced care and transport are not available. The purpose of this case series is to examine the details of these missions, review patient treatments and outcomes, and describe common tactics, techniques, and procedures for these missions. 

Methods: Cases in which the USAF PJs preformed long-range ocean rescue for critically ill or injured civilians between 2011 and 2018 were identified. Case information was obtained, including patient demographics, location, infiltration/exfiltration methods, diagnoses, treatments, duration of patient care, patient outcome, and lessons learned. 

Results: A total of 14 pararescue missions involving 22 civilians were identified for analysis. Of the 22 patients, 10 (45%) suffered burns, six (27%) had abdominal issues, four (18%) had musculoskeletal injuries, one had a traumatic brain injury, and one had a necrotizing soft-tissue infection. Medical care of these patients included intravenous fluid and blood product resuscitation, antibiotics, analgesics, airway management, and escharotomy. The median duration of patient care was 51 hours. 

Conclusion: This case series illustrates the complex transportation requirements, patient and gear logistical challenges, austere medicine, and prolonged field care (PFC) unique to USAF PJ open-water response.

Are there Field Triage Criteria that Can Predict Low-Yield Air Medical Transports?

Hiroko Miyagi, David C Evans, Howard A Werman

Prehosp Disaster Med 2019 Dec;34(6):596-603 

Abstract

Introduction: Air medical transport of trauma patients from the scene of injury plays a critical role in the delivery of severely injured patients to trauma centers. Over-triage of patients to trauma centers reduces the system efficiency and jeopardizes safety of air medical crews.

Hypothesis: The objective of this study was to determine which triage factors utilized by Emergency Medical Services (EMS) providers are strong predictors of early discharge for trauma patients transported by helicopter to a trauma center.

Methods: A retrospective chart review over a two-year period was performed for trauma patients flown from the injury site into a Level I trauma center by an air medical transport program. Demographic and clinical data were collected on each patient. Prehospital factors such as Glasgow Coma Score (GCS), Revised Trauma Score (RTS), intubation status, mechanism of injury, anatomic injuries, physiologic parameters, and any combinations of these factors were investigated to determine which triage criteria accurately predicted early discharge. Hospital factors such as Injury Severity Score (ISS), length-of-stay (LOS), survival, and emergency department disposition were also collected. Early discharge was defined as a hospital stay of less than 24 hours in a patient who survives their injuries. A more stringent definition of appropriate triage was defined as a patient with in-hospital death, an ISS >15, those taken to the operating room (OR) or intensive care unit (ICU), or those receiving blood products. Those patients who failed to meet these criteria were also used to determine over-triage rates.

Results: An overall early discharge rate of 35% was found among the study population. Furthermore, when the more stringent definition was applied, over-triage rates were as high as 85%. Positive predictive values indicated that patients who met at least one anatomic and physiologic criteria were appropriately transported by helicopter as 94% of these patients had stays longer than 24 hours. No other criteria or combination of criteria had a high predictive value for early discharge.

Conclusions: No individual triage criteria or combination of criteria examined demonstrated the ability to uniformly predict an early discharge. Although helicopter transport and subsequent hospital care is costly and resource consuming, it appears that a significant number of patients will be discharged within 24 hours of their transport to a trauma center. Future studies must determine the impact of eliminating "low-yield" triage criteria on under-triage of scene trauma patients.

Effects of hypertonic saline versus mannitol in patients with traumatic brain injury in prehospital, emergency department, and intensive care unit settings: a systematic review and meta-analysis

Yukari Miyoshi, Yutaka Kondo, Hidetaka Suzuki, Tatsuma Fukuda, Hideto Yasuda, Shoji Yokobori, Japan Resuscitation Council (JRC) Neuroresuscitation Task Force and the Guidelines Editorial Committee 

J Intensive Care. 2020 Aug 12;8:61 

Background: Intracranial pressure control has long been recognized as an important requirement for patients with severe traumatic brain injury. Hypertonic saline has drawn attention as an alternative to mannitol in this setting. The aim of this study was to assess the effects of hypertonic saline versus mannitol on clinical outcomes in patients with traumatic brain injury in prehospital, emergency department, and intensive care unit settings by systematically reviewing the literature and synthesizing the evidence from randomized controlled trials. 

Methods: We searched the MEDLINE database, the Cochrane Central Register of Controlled Trials, and the Igaku Chuo Zasshi (ICHUSHI) Web database with no date restrictions. We selected randomized controlled trials in which the clinical outcomes of adult patients with traumatic brain injury were compared between hypertonic saline and mannitol strategies. Two investigators independently screened the search results and conducted the data extraction. The primary outcome was all-cause mortality. The secondary outcomes were 90-day and 180-day mortality, good neurological outcomes, reduction in intracranial pressure, and serum sodium level. Random effects estimators with weights calculated by the inverse variance method were used to determine the pooled risk ratios. 

Results: A total of 125 patients from four randomized trials were included, and all the studies were conducted in the intensive care unit. Among 105 patients from three trials that evaluated the primary outcome, 50 patients were assigned to the hypertonic saline group and 55 patients were assigned to the mannitol group. During the observation period, death was observed for 16 patients in the hypertonic saline group (32.0%) and 21 patients in the mannitol group (38.2%). The risks were not significant between the two infusion strategies (pooled risk ratio, 0.82; 95% confidence interval, 0.49-1.37). There were also no significant differences between the two groups in the other secondary outcomes. However, the certainty of the evidence was rated very low for all outcomes. 

Conclusions: Our findings revealed no significant difference in the all-cause mortality rates between patients receiving hypertonic saline or mannitol to control intracranial pressure. Further investigation is warranted because we only included a limited number of studies.

Ketamine Safety and Use in the Emergency Department for Pain and Agitation/Delirium: A Health System Experience

Hanjie Mo, Matthew J Campbell, Baruch S Fertel, Simon W Lam, Elizabeth J Wells, Elizabeth Casserly, Stephen W Meldon

West J Emerg Med 2020 Jan 27;21(2):272-281 

Abstract

Introduction: Two protocols were developed to guide the use of subdissociative dose ketamine (SDDK) for analgesia and dissociative sedation ketamine for severe agitation/excited delirium in the emergency department (ED). We sought to evaluate the safety of these protocols implemented in 18 EDs within a large health system.

Methods: We conducted a retrospective chart review to evaluate all adult patients who received intravenous (IV) SDDK for analgesia and intramuscular (IM) dissociative sedation ketamine for severe agitation/excited delirium in 12 hospital-based and six freestanding EDs over a one-year period from the protocol implementation. We developed a standardized data collection form and used it to record patient information regarding ketamine use, concomitant medication use, and any comorbidities that could have impacted the incidence of adverse events.

Results: Approximately 570,000 ED visits occurred during the study period. SDDK was used in 210 ED encounters, while dissociative sedation ketamine for severe agitation/excited delirium was used in 37 ED encounters. SDDK was used in 83% (15/18) of sites while dissociative sedation ketamine was used in 50% (9/18) of sites. Endotracheal intubation, non-rebreather mask, and nasal cannula ≥ four liters per minute were identified in one, five, and three patients, respectively. Neuropsychiatric adverse events were identified in 4% (9/210) of patients who received SDDK.

Conclusion: Patients experienced limited neuropsychiatric adverse events from SDDK. Additionally, dissociative sedation ketamine for severe agitation/excited delirium led to less endotracheal intubation than reported in the prehospital literature. The favorable safety profile of ketamine use in the ED may prompt further increases in usage.

Impact of a 4-hour Introductory eFAST Training Intervention Among Ultrasound-Naïve U.S. Military Medics

Jonathan D Monti 1, Michael D Perreault 2

Mil Med 2020 Jun 8;185(5-6):e601-e608 

Abstract

Introduction: Advances in the portability of ultrasound have allowed it to be increasingly employed at the point of care in austere settings. Battlefield constraints often limit the availability of medical officers throughout the operational environment, leading to increased interest in whether highly portable ultrasound devices can be employed by military medics to enhance their provision of combat casualty care. Data evaluating optimal training for effective medic employment of ultrasound is limited however. This prospective observational cohort study's primary objective was to assess the impact of a 4-hour introductory training intervention on ultrasound-naïve military medic participants' knowledge/performance of the eFAST application.

Materials and methods: Conventional U.S. Army Medics, all naïve to ultrasound, were recruited from across JBLM. Volunteer participants underwent baseline eFAST knowledge assessment via a 50-question multiple-choice exam. Participants were then randomized to receive either conventional, expert-led classroom didactic training or didactic training via an online, asynchronously available platform. All participants then underwent expert-led, small group hands-on training and practice. Participants' eFAST performance was then assessed with both live and phantom models, followed by a post-course knowledge exam. Concurrently, emergency medicine (EM) resident physician volunteers, serving as standard criterion for trained personnel, underwent the same OSCE assessments, followed by a written exam to assess their baseline eFAST knowledge. Primary outcome measures included (1) post-course knowledge improvement, (2) eFAST exam technical adequacy, and (3) eFAST exam OSCE score. Secondary outcome measures were time to exam completion and diagnostic accuracy rate for hemoperitoneum and hemopericardium. These outcome measures were then compared across medic cohorts and to those of the EM resident physician cohort.

Results: A total of 34 medics completed the study. After 4 hours of ultrasound training, overall eFAST knowledge among the 34 medics improved from a baseline mean of 27% on the pretest to 83% post-test. For eFAST exam performance, the medics scored an average of 20.8 out of a maximum of 22 points on the OSCE. There were no statistically significant differences between the medics who received asynchronous learning versus traditional classroom-based learning, and the medics demonstrated comparable performance to previously trained EM resident physicians.

Conclusions: A 4-hour introductory eFAST training intervention can effectively train conventional military medics to perform the eFAST exam. Online, asynchronously available platforms may effectively mitigate some of the resource requirement burden associated with point-of-care ultrasound training. Future studies evaluating medic eFAST performance on real- world battlefield trauma patients are needed. Skill and knowledge retention must also be assessed for this degradable skill to determine frequency of refresher training when not regularly performed.

Intraosseous access in adults in cardiac arrest: a systematic review and meta-analysis

Ignacio Morales-Cané, María Del Rocío Valverde-León, María Aurora Rodríguez-Borrego, Pablo Jesús López-Soto

Emergencias 2020 Feb;32(1):49-56. 

Abstract

Objectives: To evaluate the efficacy of intraosseous access versus venous access in out-of- hospital cardiac arrest in terms of return of spontaneous circulation (ROSC) and survival to hospital discharge with or without favorable neurologic status.

Material and methods: Systematic review and meta-analysis of articles indexed in MEDLINE (PubMed), Embase, the Web of Science, and the Cochrane Library. Other terms adapted to the language of each index were also used. We included observational studies and clinical trials published from January 1, 1950, to May 31, 2019, if the study population included adult patients in cardiac arrest outside the hospital and in whom an intraosseous or intravenous catheter was inserted. Risk of bias was evaluated with the Cochrane and GRADE (Grading of Recommendations Assessment, Development and Evaluation) tools.

Results: We identified 434 papers to include in the qualitative review and 5 studies for meta- analysis. Intraosseous access was related to a lower rate of ROSC (odds ratio [OR], 0.69; 95% CI, 0.57-0.83; P=.02; I2=65%) and worse survival to discharge (OR, 0.65; 95% CI, 0.51-0.83); P<.01, I2=30%).

Conclusion: Intraosseous access in out-of-hospital cardiac arrest is related to poorer outcomes in terms of ROSC and survival at hospital discharge.

Keywords: Circulación espontánea; Alta hospitalaria; Hospital discharge; Intraosseous catheter; Spontaneous circulation; Vía intraósea.

Evaluation of prolonged 'Permissive Hypotension': results from a 6-hour hemorrhage protocol in swine

Clifford G Morgan, Leslie E Neidert, Emily N Hathaway, Gerardo J Rodriguez, Leasha J Schaub, Sylvain Cardin, Jacob J Glaser

Trauma Surg Acute Care Open 2019 Nov 21;4(1):e000369 

Abstract

Background: Tactical Combat Casualty Care guidelines for hemorrhage recommend resuscitation to systolic blood pressure (SBP) of 85±5 mm Hg during prehospital care. Success depends on transport to definitive care within the 'golden hour'. As future conflicts may demand longer prehospital/transport times, we sought to determine safety of prolonged permissive hypotension (PH).

Methods: Adult male swine were randomized into three experimental groups. Non-shock (NS)/normotensive underwent anesthesia only. NS/PH was bled to SBP of 85±5 mm Hg for 6 hours of prolonged field care (PFC) with SBP maintained via crystalloid, then recovered.

Experimental group underwent controlled hemorrhage to mean arterial pressure 30 mm Hg until decompensation (Decomp/PH), followed by 6 hours of PFC. Hemorrhaged animals were then resuscitated with whole blood and observed for 24 hours. Physiologic variables, blood, tissue samples, and neurologic scores were collected.

Results: Survival of all groups was 100%. Fluid volumes to maintain targeted SBP in PFC were significantly higher in the hemorrhage group than sham groups. After 24 hours' recovery, no significant differences were observed in neurologic scores or cerebrospinal fluid markers of brain injury. No significant changes in organ function related to treatment were observed during PFC through recovery, as assessed by serum chemistry and histological analysis.

Conclusions: After 6 hours, a prolonged PH strategy showed no detrimental effect on survival or neurologic outcome despite the increased ischemic burden of hemorrhage. Significant fluid volume was required to maintain SBP-a potential logistic burden for prehospital care. Further work to define maximum allowable time of PH is needed.

Ketamine Use in Prehospital and Hospital Treatment of the Acute Trauma Patient: A Joint Position Statement

Margaret M Morgan, Debra G Perina, Nicole M Acquisto, Mary E Fallat, John M Gallagher, Kathleen M Brown, Jeffrey Ho, Aaron Burnett, Julio Lairet, Dennis Rowe, Mark L Gestring

Prehosp Emerg Care. 2020 Aug 27;1-5. doi: 10.1080/10903127.2020.1801920. Online ahead of print.

Abstract 

The American College of Surgeons Committee on Trauma (ACS-COT), the American College of Emergency Physicians (ACEP), the National Association of State EMS Officials (NASEMSO), the National Association of EMS Physicians (NAEMSP) and the National Association of EMTs (NAEMT) have previously offered varied guidance on the use of ketamine in trauma patients. The following consensus statement represents the collective positions of the ACS-COT, ACEP, NASEMSO, NAEMSP and NAEMT. This updated uniform guidance is intended for use by emergency medical services (EMS) personnel, EMS medical directors, emergency physicians, trauma surgeons, nurses and pharmacists in their treatment of the trauma patient in both the prehospital and hospital setting.

Resuscitation After Hemorrhagic Shock in the Microcirculation: Targeting Optimal Oxygen Delivery in the Design of Artificial Blood Substitutes

Carlos Munoz, Federico Aletti, Krianthan Govender, Pedro Cabrales, Erik B Kistler 

Front Med (Lausanne). 2020 Oct 27;7:585638. doi: 10.3389/fmed.2020.585638. eCollection 2020 

Abstract 

Microcirculatory preservation is essential for patient recovery from hemorrhagic shock. In hemorrhagic shock, microcirculatory flow and pressure are greatly reduced, creating an oxygen debt that may eventually become irreversible. During shock, tissues become hypoxic, cellular respiration turns to anaerobic metabolism, and the microcirculation rapidly begins to fail. This condition requires immediate fluid resuscitation to promote tissue reperfusion. The choice of fluid for resuscitation is whole blood; however, this may not be readily available and, on a larger scale, may be globally insufficient. Thus, extensive research on viable alternatives to blood has been undertaken in an effort to develop a clinically deployable blood substitute. This has not, as of yet, achieved fruition, in part due to an incomplete understanding of the complexities of the function of blood in the microcirculation. Hemodynamic resuscitation is acknowledged to be contingent on a number of factors other than volume expansion. The circulation of whole blood is carefully regulated to optimize oxygen delivery to the tissues via shear stress modulation through blood viscosity, inherent oxygen-carrying capacity, cell-free layer variation, and myogenic response, among other variables. Although plasma expanders can address a number of these issues, hemoglobin-based oxygen carriers (HBOCs) introduce a method of replenishing the intrinsic oxygen-carrying capacity of blood. There continue to be a number of issues related to HBOCs, but recent advances in the next-generation HBOCs show promise in the preservation of microcirculatory function and limiting toxicities. The development of HBOCs is now focused on viscosity and the degree of microvascular shear stress achieved in order to optimize vasoactive and oxygen delivery responses by leveraging the restoration and maintenance of physiological responses to blood flow in the microcirculation. Blood substitutes with higher viscous properties tend to improve oxygen delivery compared to those with lower viscosities. This review details current concepts in blood substitutes, particularly as they relate to trauma/hemorrhagic shock, with a specific focus on their complex interactions in the microcirculation.

 

Tranexamic acid adverse reactions: a brief summary for internists and emergency doctors

Giuseppe Murdaca, Monica Greco, Chiara Vassallo, Sebastiano Gangemi 

Clin Mol Allergy. 2020 Sep 3;18:16 

Abstract 

Tranexamic acid (TXA) is a synthetic lysine analogue that is well known as antifibrinolytic agent. It can reduce blood loss in clinical use, especially in conditions where fibrinolysis or hyperfibrinolysis are involved, such as trauma or surgery. Moreover, TXA has been approved as second-line prophylactic therapy for hereditary angioedema and further data have been published about a possible use of TXA as maintenance treatment for nonhistaminergic angioedema and treatment for episodes of bradykinin-mediated angioedema induced by ACE inhibitors. TXA can be administered through several routes: orally, topically, or intravenously. Although, it is a drug with a very high safety profile, in few cases hypersensitivity reactions have been described occurring with different clinical manifestations. Ethamsylate can be an alternative in TXA sensitized patients. In this brief article we describe TXA adverse reactions and current protocols which have been proposed to help clinicians to diagnose TXA hypersensitivity.

Just the facts: Hypertonic saline is just as good as (and probably better than) mannitol

Laurel Murphy

CJEM 2020 Mar;22(2):152-154 

Abstract

A 27-year-old female is brought to the emergency department (ED) by ambulance following a motor vehicle collision at highway speed. She was the belted driver. She has no significant past medical history and is on no medications. Following a prolonged extrication, she is intubated due to decreased level of consciousness before transport.

The good, the bad and the ugly of point-of-care ultrasound

Alistair Murray

Emerg Med Australas 2020 Feb;32(1):158-159 

The use of focussed ultrasound (US) or point-of-care ultrasound (POCUS) has changed significantly over the years, as has the way we learn US: from attending workshops to accessing multiple online resources and increasingly realistic simulators. The knowledge and understanding of the ways we learn has developed with it the need for deliberate practice, spaced repetition and meaningful feedback. With these advances there are significant challenges in trying to ascertain what level of proficiency we have attained. We know that self- assessment is deeply unreliable, for example, if you were to ask a room full of people, ‘Please raise your hand if you think you are an above average driver’, it can be practically guaranteed that over 50% of the room will raise their hand. Experience alone is not enough, or else we would award FACEM upon completion of rotations, without the need for examinations or in- training assessments.

Is prehospital use of active external warming dangerous for patients with accidental hypothermia: a systematic review

Sigurd Mydske, Øyvind Thomassen

Scand J Trauma Resusc Emerg Med. 2020 Aug 10;28(1):77

Abstract 

Background: Optimal prehospital management and treatment of patients with accidental hypothermia is a matter of frequent debate, with controversies usually revolving around the subject of rewarming. The rule of thumb in primary emergency care and first aid for patients with accidental hypothermia has traditionally been to be refrain from prehospital active rewarming and to focus on preventing further heat loss. The potential danger of active external rewarming in a prehospital setting has previously been generally accepted among the emergency medicine community based on a fear of potential complications, such as "afterdrop", "rewarming syndrome", and "circum-rescue collapse". This has led to a reluctancy from health care providers to provide patients with active external rewarming outside the hospital. Different theories and hypotheses exist for these physiological phenomena, but the scientific evidence is limited. The research question is whether the prehospital use of active external rewarming is dangerous for patients with accidental hypothermia. This systematic review intends to describe the acute unfavourable adverse effects of active external rewarming on patients with accidental hypothermia. 

Methods: A literature search of the Cochrane Library, MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL], and SveMed+ was carried out, and all articles were screened for eligibility. All article formats were included. 

Results: Two thousand three hundred two articles were screened, and eight articles met our search criteria. Three articles were case reports or case series, one was a prospective study, two were retrospective studies, one article was a literature review, and one article was a war report from the Napoleonic Wars. 

Conclusions: One of the main findings in this article was the poor scientific quality and the low number of articles meeting our inclusion criteria. When conducting this review, we found no scientific evidence of acceptable quality to prove that the use of active external rewarming is dangerous for patients with accidental hypothermia in a prehospital setting. We found several articles claiming that active external rewarming is dangerous, but most of them do not cite references or provide evidence.

Prolonged Use of Supraglottic Airway Device for Mechanical Ventilation in the Intensive Care Unit

Shagufta Naaz, Nishant Sahay, Rajnish Kumar, Amarjeet Kumar, Adil Asghar

Indian J Crit Care Med. 2020 Oct;24(10):1001-1002 

No Abstract

Assessment of the Efficacy and Safety of a Novel, Low-Cost, Junctional Tourniquet in a Porcine Model of Hemorrhagic Shock

Dean Nachman, Dor Dulce, Linn Wagnert-Avraham, Lilach Gavish, Noy Mark, Rafi Gerrasi, S David Gertz, Arik Eisenkraft 

Mil Med. 2020 Jan 7;185(Suppl 1):96-102 

Introduction: Commercially available junctional tourniquets (JTQs) have several drawbacks. We developed a low-cost, compact, easy to apply JTQ. The aim of this study was to assess the tourniquets' safety and efficacy in a swine model of controlled hemorrhage. 

Materials and methods: Five pigs were subjected to controlled bleeding of 35% of their blood volume. Subsequently, the JTQ was applied to the inguinal area for 180 minutes. Afterwards, the tourniquet was removed for additional 60 minutes of follow up. During the study, blood flow to both hind limbs and blood samples for tissue damage markers were repeatedly assessed. Following sacrifice, injury to both inguinal areas was evaluated microscopically and macroscopically. 

Results: Angiography demonstrated complete occlusion of femoral artery flow, which was restored following removal of the tourniquet. No gross signs of tissue damage were noticed. Histological analysis revealed mild necrosis and infiltration of inflammatory cells. Blood tests showed a mild increase in potassium and lactic acid levels throughout the protocol. 

Conclusions: The tourniquet achieved effective arterial occlusion with minimal tissue damage, similar to reports of other JTQs. Subjected to further human trials, the tourniquet might be a suitable candidate for widespread frontline deployment because of its versatility, compactness, and affordable design.

Freeze dried plasma for the resuscitation of traumatized pediatric patients: Response

Roy Nadler, Yael Mozer-Glassberg, Barbara Gaines, Elon Glassberg, Jacob Chen

J Trauma Acute Care Surg 2020 Jun;88(6):e152-e153 

While the use of shock index was previously considered as a threshold for blood products use in adults, the Israeli Defense Forces (IDF) current clinical practice guidelines (CPGs) refer to blood pressure and heart rate thresholds. These thresholds are also used by other prehospital systems (1,2). We agree that standard pediatric specific-specific thresholds for prehospital resuscitation with blood products are lacking (3), however, it is important to note that reconstituted FDP is the resuscitation fluid of choice in the IDF, obviating the use of crystalloids. Thus, reconstituted FDP is used mainly to restore lost volume, rather than replacing clotting factors.

Early experience with transfusing low titer group O whole blood in the pre-hospital setting in Israel

Roy Nadler, Avishai M Tsur, Mark H Yazer, Eilat Shinar, Tzadok Moshe, Avi Benov, Elon Glassberg, Danny Epstein, Jacob Chen

Transfusion 2020 Jun;60 Suppl 3:S10-S16 

Background: The Israeli Defense Force Medical Corps (IDF-MC) recently implemented the use of low titer group O whole blood (LTOWB) in the airborne combat search and rescue unit (CSAR) for both military and civilian patients during transport to definitive care. LTOWB is preferentially used by the CSAR instead of red blood cell units and freeze-dried plasma (FDP) for patients with signs of hemorrhagic shock. Ten percent of group O donors were eligible to donate LTOWB as they had anti-A and -B IgM titers of <50.

Methods: All patients treated by CSAR providers with LTOWB between July 2018 and June 2019 were included.

Results: Between July 2018 and June 2019, eight patients have received 10 units of LTOWB. All patients suffered blunt injuries, 6 out of 8 (75%) of whom were due to motor vehicle accidents. Four patients (4 out of 8, 50%) received a single LTOWB unit, two patients (2 out of 8, 25%) received two units. Two pediatric patients received fewer than one unit of LTOWB. Median (range) heart rate was 130 (30-150) bpm, median systolic blood pressure was 107 (80- 124) mmHg, and median Glasgow coma scale was 8 (on a scale of 3-15). For four (4 out of 8, 50%) patients, LTOWB was the only blood product used for volume resuscitation. All six adult patients were treated with 1 g of tranexamic acid at the point of injury.

Conclusions: The CSAR has successfully implemented a LTOWB program for the pre-hospital treatment of bleeding patients, and as its experience grows this product will be made available to other units and in civilian hospitals.

The importance of simulation education for the management of traumatic cardiac injuries: a case series

Takashi Nagata, Tomohiko Akahoshi, Michiko Sugino, Wataru Ishii, Ryoji Iizuka, Takafumi Shinjo, Yoshimitsu Izawa, Michiaki Hata, Alan Kawarai Lefor

Surg Case Rep 2019 Dec 20;5(1):202 

Abstract

Background: The management of cardiac trauma requires rapid intervention in the emergency room, facilitated by a surgeon with prior experience to have good outcomes. Many surgeons have little experience in the requisite procedures. We report here 4 patients who suffered cardiac trauma, and all 4 patients survived with good neurologic outcomes.

Case presentations: Patient 1 suffered blunt cardiac trauma from a motor vehicle accident and presented in shock. Cardiac tamponade was diagnosed and a cardiac rupture repaired with staples through a median sternotomy after rapid transport to the operating room. Patient 2 suffered blunt cardiac trauma and presented in shock with cardiac tamponade. Operating room median sternotomy allowed extraction of pericardial clot with recovery of physiologic stability.

Patient 3 presented with self-inflicted stab wounds to the chest and was unstable. She was brought to the operating room and thoracotomy allowed identification of a left ventricle wound which was repaired with a suture. Patient 4 presented in cardiac arrest with multiple self-inflicted stab wounds to the chest. Emergency room thoracotomy allowed repair of a right ventricle laceration with recovery of vital signs.

Conclusions: The management of all 4 patients was according to the principles taught in the ATOM course. Three of the 4 surgeons had no prior experience with management of cardiac trauma and credited the good outcomes to taking the ATOM course. These are uncommon injuries and formal training in their management is beneficial to patients.

Evidence review for intravenous fluid management strategy: Perioperative care in adults

National Guideline Centre (UK)

London: National Institute for Health and Care Excellence (UK); 2020 Aug. 

Excerpt 

The type of fluid administered in the perioperative period can have a significant effect on outcomes in patients have major surgery. There has been considerable debate over the safety and efficacy of crystalloids versus colloids. The key difference between crystalloids and colloids is that the colloids contain much larger molecules than that of crystalloids. Crystalloids are aqueous solutions of salts, minerals or any other water-soluble substances, for example, saline. Colloid solutions include hetastarch, dextran and plasma protein solutions. Since they are remaining in the vascular system, colloids are much more effective to use for expanding the circulatory volume than crystalloids. However, excessive use of colloids has been associated with side effects such as peripheral and pulmonary oedema and cardiac failure.

Recent evidence has been identified to address the question on the clinical and cost effectiveness of crystalloids versus colloids. The aim of this review is to perform a systematic review collating all of the relevant evidence.

Pediatric Prehospital Wound Prophylaxis in Iraq and Afghanistan

Jason F Naylor, Michael D April, Guyon J Hill, Steven G Schauer Mil Med 2020 Jan 7;185(Suppl 1):73-76 

Abstract

Background: Infectious complications of war wounds are a significant source of mortality and morbidity. Tactical Combat Casualty Care (TCCC) guidelines recommend prehospital moxifloxacin, ertapenem, or cefotetan for "all open combat wounds." We describe the prehospital administration of antibiotics to pediatric trauma patients.

Methods: We queried the Department of Defense Trauma Registry for all pediatric subjects admitted to United States and Coalition fixed-facility hospitals in Iraq and Afghanistan from January 2007 to January 2016.

Results: During this time, there were 3,439 pediatric encounters which represented 8.0% of all admissions. Prehospital providers administered a total of 216 antibiotic doses to 210 subjects. Older children received antibiotics more frequently than younger children, were more likely to be male, located in Afghanistan, and injured by explosive with the majority surviving to hospital discharge. Cefazolin and ceftriaxone were the most frequently utilized antibiotics.

Conclusions: The most frequently administered antibiotics were cephalosporins. TCCC recommended agents for adult prehospital wound prophylaxis were infrequently administered to pediatric casualties. Administration rates of pediatric prehospital wound prophylaxis may be improved with pediatric-specific TCCC guidelines recommending cephalosporins as first-line agents, fielding of a TCCC-oriented Broselow tape, and training prehospital providers on administration of antimicrobials.

An analysis of radial pulse strength to recorded blood pressure in the Department of Defense Trauma Registry

Jason F Naylor, Andrew D Fisher, Michael D April, Steven G Schauer 

Mil Med. 2020 Dec 30;185(11-12):e1903-e1907 

Introduction: Hemorrhage is the leading cause of potentially preventable death on the battlefield. The tactical combat casualty care guidelines recommend the use of the radial pulse strength to guide the administration of blood products or intravenous fluids when equipment for blood pressure monitoring is not available. Data supporting this measurement tool are limited. We sought to validate this method in a deployed trauma population. 

Materials and methods: This is a secondary analysis of a previously published dataset from the Department of Defense Trauma Registry. In this subanalysis, we focused on emergency department radial pulse strength documented in conjunction with systolic blood pressure readings. 

Results: Our predefined search codes captured 28,222 Department of Defense Trauma Registry casualties. Of those, 22,192 casualties had at least 1 radial pulse strength documented, with a total of 27,366 documented measurements total among the 22,192. The median age of casualties was 25 years, most were male (96.8%), U.S. military made up the largest proportion (44.2%), most were injured by explosive (55.8%), and most were in Afghanistan (67.0%) with a median injury severity score of 9. Mean systolic blood pressures were significantly different based on radial pulse strength: strong (129.6), weak (107.5), and absent (85.1). However, when using a binary threshold of 80 mmHg, there were 615 documented instances of hypotension. Within that 615, 55.6% had a strong radial pulse, 29.3% had a weak radial pulse, and 15.1% had an absent radial pulse (P < .001). 

Conclusions: Although mean systolic blood pressure was associated with radial pulse quality, when using a binary measurement of hypotension (systolic < 80 mmHg) characterization of the radial pulse was not a reliable indicator of hypotension. Better methods for casualty monitoring must be employed to avoid missing opportunities for intervention.

Prehospital Transfusion of Low-Titer O + Whole Blood for Severe Maternal Hemorrhage: A Case Report

Ryan Newberry, C J Winckler, Ryan Luellwitz, Leslie Greebon, Elly Xenakis, William Bullock, Michael Stringfellow, Julian Mapp

Prehosp Emerg Care Jul-Aug 2020;24(4):566-575 

Abstract

Introduction: Beginning in 2017, multiple stakeholders within the Southwest Texas Regional Advisory Council for Trauma collaborated to incorporate cold-stored low-titer O RhD-positive whole blood (LTO + WB) into all phases of their trauma system, including the prehospital phase of care. Although the program was initially focused on trauma resuscitation, it was expanded to included non-traumatic hemorrhagic shock patients that may benefit from whole blood resuscitation.

Case Report: We report the case of a patient with severe maternal hemorrhage secondary to placenta accreta who received a prehospital transfusion of LTO + WB. We believe this to be the first reported case of post-partum hemorrhage resuscitated out of hospital with whole blood.

Discussion: This case highlights the potential benefits of a prehospital whole blood program as well as the controversy surrounding a LTO + WB program that includes females of childbearing age.

Timely access to care for patients with critical burns in India: a prehospital prospective observational study

Jennifer A Newberry, Corey B Bills, Elizabeth A Pirrotta, Michele Barry, Govindaraju Venkata Ramana Rao, Swaminatha V Mahadevan, Matthew C Strehlow

Emerg Med J 2019 Mar;36(3):176-182

Abstract

Background: Low/middle-income countries carry a disproportionate burden of the morbidity and mortality from thermal burns. Nearly 70% of burn deaths worldwide are from thermal burns in India. Delays to medical care are commonplace and an important predictor of outcomes. We sought to understand the role of emergency medical services (EMS) as part of the healthcare infrastructure for thermal burns in India.

Methods: We conducted a prospective observational study of patients using EMS for thermal burns across five Indian states from May to August 2015. Our primary outcome was mortality at 2, 7 and 30 days. We compared observed mortality with expected mortality using the revised Baux score. We used Χ2 analysis for categorical variables and Wilcoxon two-sample test for continuous variables. ORs and 95% CIs are reported for all modelled predictor variables.

Results: We enrolled 439 patients. The 30-day follow-up rate was 85.9% (n=377). The median age was 30 years; 56.7% (n=249) lived in poverty; and 65.6% (n=288) were women. EMS transported 94.3% of patients (n=399) to the hospital within 2 hours of their call. Median total body surface area (TBSA) burned was 60% overall, and 80% in non-accidental burns. Sixty- eight per cent of patients had revised Baux scores greater than 80. Overall 30-day mortality was 64.5%, and highest (90.2%) in women with non-accidental burns. Predictors of mortality by multivariate regression were TBSA (OR 7.9), inhalation injury (OR 5.5), intentionality (OR 4.7) and gender (OR 2.2).

Discussion: Although EMS rapidly connects critically burned patients to care in India, mortality remains high, with women disproportionally suffering self-inflicted burns. To combat the burn epidemic in India, efforts must focus on rapid medical care and critical care services, and on a burn prevention strategy that includes mental health and gender-based violence support services.

Introduction of a mass burn casualty triage system in a hospital during a powder explosion disaster: a retrospective cohort study

Chip-Jin Ng, Shih-Hao You, I-Lin Wu, Yi-Ming Weng, Chung-Hsien Chaou, Cheng-Yu Chien, Chen-June Seak

World J Emerg Surg 2018 Aug 29;13:38

Abstract

Background: The triage system used during an actual mass burn casualty (MBC) incident is a major focus of concern. This study introduces a MBC triage system that was used by a burn center during an actual MBC incident following a powder explosion in New Taipei City, Taiwan.

Methods: This study retrospectively analyzed data from patients who were sent to the study hospital during a MBC incident. The patient list was retrieved from a national online management system. A MBC triage system was developed at the study hospital using the following modifiers: consciousness, breathing, and burn size. Medical records were retrieved from electronic records for analysis. Patient outcomes consisted of emergency department (ED) disposition and intervention.

Results: The patient population was predominantly female (56.3%), with an average age of 24.9 years. Mean burn sizes relative to the TBSA of triage level I, II, and III patients were 57.9%, 40.5%, and 8.7%, respectively. ICU length of stay differed markedly according to triage level (mean days for levels I vs II vs III: 57.9 vs 39.9 vs 2.5 days; p < 0.001). Triage system levels I and II indicate ICU admission with a sensitivity of 93.9% (95%CI 80.4-98.3%) and a specificity of 86.7% (62.1-96.3%).Overall, 3 (6.3%) patients were under-triaged. Two (4.2%) patients were over-triaged. Sixteen (48.5%) and 21 (63.6%) patients of triage levels I and II received endotracheal intubation and central venous catheterization, respectively. Sorting of the study population with simple triage and rapid treatment (START) showed great sensitivity (100.0%) but poor specificity (53.3%). The Taiwan Triage and Acuity Scale (TTAS) presented 87.9% sensitivity and 93.9% specificity.

Conclusions: The current MBC triage algorithm served as a good indicator of ED disposition but might have raised excessive immediate attention and had the potential to exhaust the available resources. These findings add to our knowledge of the MBC triage system and should help future researchers in adjusting the triage criteria to fit actual disasters.

Editorial on the Approach to Prolonged Field Care for the Special Forces Medical Sergeant: Balancing the Opportunity Cost

James A Nicholson, Justin N Searor, Andrew D Lane 

J Spec Oper Med. Fall 2020;20(3):117-119 

Abstract 

America's adversaries will contest US military superiority in the domains of land, sea, air, space, and cyberspace. Fundamentally, these foes seek to disrupt the dominance of American fighting forces through anti-access and area denial (A2AD) systems, such as cyber exploitation, electromagnetic jamming, air defense networks, and hypersonic capabilities. According to Training and Doctrine Command (TRADOC) Pamphlet 525- 3-1, these A2AD capabilities create multiple layers of stand-off that inhibit the US ability to focus combat power and achieve strategic objectives in a contested, increasingly lethal, inherently complex, and challenging operational environment.1 The Department of Defense (DoD) plans to mitigate this shift in enemy strategy through the adoption of multidomain operations (MDO).1 MDO is defined as operations that converge capabilities to overcome an adversary's strengths across various domains by imposing simultaneous dilemmas that achieve operational and tactical objectives.1 Within this MDO construct, medical treatment expectations must shift accordingly as the ability to rapidly treat and evacuate patients may be constrained by enemy action. Thus, the notion of prolonged field care (PFC) may be a necessity on the future battlefield. As Special Operations Forces (SOF) continue to refine what PFC entails, it is imperative that an understanding of the incidence and type of diseases that require medical evacuation to higher levels of care be thoughtfully estimated. Armed with an understanding of the anticipated epidemiology, effective prioritization of training requirements and equipment acquisition is possible in a manner that is complementary to the overall success of the assigned mission. Furthermore, this prior planning mitigates risk, as the limitations of money and time impose significant opportunity costs in the short run should the disproportionate mix of disease states be pursued, which in turn, avoids jeopardizing Soldiers' lives over the long term.

Patient Contact Time and Prehospital Interventions in Hypotensive Trauma Patients: Should We Reconsider the "ABC" Algorithm When Time Is of the Essence?

Scott Ninokawa, Jessica Friedman, Danielle Tatum, Alison Smith, Sharven Taghavi, Patrick McGrew, Juan Duchesne

 Am Surg. 2020 Aug;86(8):937-943 

Introduction: There is disagreement in the trauma community concerning the extent to which emergency medical services (EMS) should perform on-scene interventions. Additionally, in recent years the "ABC" algorithm has been questioned in hypotensive patients. The objective of this study was to quantify the delay introduced by different on-scene interventions. 

Methods: A retrospective analysis of hypotensive trauma patients brought to an urban level 1 trauma center by EMS from 2007 to 2018 was performed, and patients were stratified by mechanism of injury and new injury severity score (NISS). Independent samples median tests were used to compare median on-scene times. 

Results: Among 982 trauma patients, median on-scene time was 5 minutes (interquartile range 3-8). In penetrating trauma patients (n = 488) with NISS of 16-25, intubation significantly increased scene time from 4 to 6 minutes (P < .05). In penetrating trauma patients with NISS of 10-15, wound care significantly increased scene time from 3 to 6 minutes (P < .05). Tourniquet use, interosseous (IO) access, intravenous (IV) access, and needle decompression did not significantly increase scene time. 

Conclusion: Understanding that intubation increases scene time in penetrating trauma, while IV and IO access do not, alterations to the traditional "ABC" algorithm may be warranted. Further investigation of prehospital interventions is needed to determine which are appropriate on-scene.

Sufentanil sublingual tablet system versus oral oxycodone for management of postoperative pain in enhanced recovery after surgery pathway for total knee arthroplasty: a randomized controlled study

Emmanuel Noel, Luca Miglionico, Mickael Leclercq, Harold Jennart, Jean-François Fils, Nicolas Van Rompaey 

J Exp Orthop. 2020 Nov 20;7(1):92 

Purpose: Effectiveness of sufentanil sublingual tablet system (SSTS) compared to oral oxycodone in the management of postoperative pain after total knee arthroplasty (TKA) within an enhanced recovery after surgery (ERAS) protocol. 

Methods: This pragmatic, parallel, open label, randomized controlled, trial enrolled 72 adult patients scheduled for TKA under spinal anesthesia following ERAS pathway. In addition to multimodal analgesia, patients received SSTS 15 mcg (SSTS group) or oral oxycodone extended release 10 mg twice daily and oral oxycodone immediate-release 5 mg up to four times daily on demand (Oxy group) to control pain during 48 h postoperatively. The primary endpoint was pain measured using a numeric rating scale at 24 h postoperatively. Time to first mobilization, side effects and patient satisfaction were also recorded. 

Results: Median pain score at 24 h at rest was 3 [2-4] for Oxy group vs 2 [1.75-3] for SSTS group (p = 0.272) whereas median pain score on movement was 4 [3-6] vs 3 [2-5] respectively (p = 0.059). No difference in time to first mobilization was found between the two groups. The method of pain control was judged good/excellent for 83.9% of patients in the SSTS group compared with 52.9% in the Oxy group (p = 0.007). The incidence of nausea was 33% in SSTS group and 9% in Oxy group (p = 0.181). 

Conclusions: In complement to ERAS multimodal analgesia, sublingual sufentanil 15 mcg tablet system did not show clinically significant pain improvement compared to oral oxycodone after total knee arthroplasty.

Causes of Delay During Interfacility Transports of Injured Patients Transported by Air Ambulance

Brodie Nolan, Barbara Haas, Homer Tien, Refik Saskin, Avery Nathens Prehosp Emerg Care 2019 Nov 11;1-9 Online ahead of print.

Abstract

Background: Many severely injured patients are initially brought to a non-trauma centers for initial assessment and stabilization. Air ambulance services are commonly used to expedite interfacility transport of injured patients to trauma centers. Little is known of the types of delays experienced during interfacility transports. The purpose of this study was to identify specific causes of modifiable delays and estimate the attributable time associated with each of these delays.

Methods: This was a retrospective cohort study of injured patients undergoing interfacility transfer to a trauma center who were transported by a provincial air ambulance service between January 1, 2014 and December 31, 2016. Electronic patient care records were screened and then manually reviewed to identify causes of delay during the interfacility transport process. The attributable time for each of these delays was also estimated.

Results: There were 932 injured patients emergently transported by air ambulance from a community hospital to a trauma center over the 3-year study period from which 458 unique causes of delay that were identified. The most frequent cause of delays to sending facility were refueling (38%), waiting for land emergency medical services escort (25%) and weather (12%). The most common in-hospital delays included waiting for documentation (32%), delay to intubate (15%), medically unstable patient (13%) and waiting for diagnostic imaging (12%). The most frequent delays to receiving/handover included waiting for land EMS escort (31%), trauma team not assembled (24%) and weather (17%). In-hospital delays with the longest average length of delay included chest tube insertion (53 minutes), intubation (49 minutes) and delays for diagnostic imaging (46 minutes).

Conclusions: In conclusion, we identified numerous modifiable causes of delay during interfacility transport. Efforts to reduce these delays can be made at both the air ambulance and hospital levels.

Comparison of 10- versus 14-gauge angiocatheter for treatment of tension pneumothorax and tension-induced pulseless electrical activity with hemorrhagic shock: Bigger is still better

Emily A Norris, Christian S McEvoy, Matthew L Leatherman, Michael R Boboc, Jamie L Fitch, Shane D Jensen, Travis M Polk

J Trauma Acute Care Surg 2020 Aug;89(2S Suppl 2):S132-S136 

Background: Little is known regarding the effect of hemorrhagic shock on the diagnosis and treatment of tension pneumothorax (tPTX). Recently, the Tactical Combat Casualty Care guidelines included the 10-gauge angiocatheter (10-g AC) as an acceptable alternative to the 14-g AC. This study sought to compare these two devices for decompression of tPTX and rescue from tension-induced pulseless electric activity (tPEA) in the setting of a concomitant 30% estimated blood volume hemorrhage.

Methods: Following a controlled hemorrhage, carbon dioxide was insufflated into the chest to induce either tPTX or tPEA. Tension pneumothorax was defined as a reduction in cardiac output by 50%, and tPEA was defined as a loss of arterial waveform with mean arterial pressure less than 20 mm Hg. The affected hemithorax was decompressed using a randomized 14-g AC or 10-g AC while a persistent air leak was maintained after decompression. Successful rescue from tPTX was defined as 80% recovery of baseline systolic blood pressure, while successful return of spontaneous circulation following tPEA was defined as a mean arterial pressure greater than 20 mm Hg. Primary outcome was success of device.

Results: Eighty tPTX and 50 tPEA events were conducted in 38 adult Yorkshire swine. There were no significant differences in the baseline characteristics between animals or devices. In the tPTX model, the 10-g AC successfully rescued 90% of events, while 14-g AC rescued 80% of events (p = 0.350). In the tPEA model, the 10-g AC rescued 87% of events while the 14 AC rescued only 48% of events (p = 0.006).

Conclusion: The 10-g AC was vastly superior to the 14-g AC for return of spontaneous circulation following tPEA in the setting of 30% hemorrhage. These findings further support the importance of larger caliber devices that facilitate rapid recovery from tPTX, particularly in the setting of polytrauma.

Diagnostic performance of prehospital ultrasound diagnosis for traumatic pneumothorax by a UK Helicopter Emergency Medical Service

Prudence Oliver, Peter Bannister, Duncan Bootland, Richard M Lyon Eur J Emerg Med 2020 Jun;27(3):202-206

Objective: Up to 20% of major trauma patients may sustain a pneumothorax. Traumatic pneumothoraces can be difficult to diagnose on scene. Although the use of handheld ultrasound (HHUS) is becoming increasingly widespread, there remains uncertainty about its efficacy as a diagnostic tool in the prehospital setting. The aim of this study was to determine the diagnostic performance of prehospital chest HHUS in trauma patients.

Method: Retrospective review of trauma patients who received a prehospital chest HHUS and subsequently conveyed to the Royal Sussex County Hospital (RSCH) between 1 July 2013 and 24 September 2018. Data including patient age, sex, mechanism of injury and clinical interventions were obtained. Prehospital ultrasound findings were compared with the computer tomography (CT) scan performed on arrival at the hospital.

Results: Four hundred eleven patients were conveyed to RSCH, the single largest group being following road traffic collisions. The majority of HHUS (66%) were performed by doctors. Three hundred sixty-one patients (88%) subsequently had a CT scan. Of these, 98 patients (27%) were found to have pneumothoraces. For pneumothorax diagnosis, prehospital HHUS had a sensitivity of 28% [95% confidence interval (CI): 19-37%] and specificity of 98% [95% CI: 97-99%].

Conclusion: In this retrospective study, sensitivity of prehospital HHUS for diagnosing a pneumothorax was lower than is often reported in in-hospital studies. This suggests that caution should be exercised in using HHUS for the exclusion of pneumothorax in the prehospital setting.

Impact of an Extraglottic Device on Pediatric Airway Management in an Urban Prehospital System

Daniel G Ostermayer, Elizabeth A Camp, James R Langabeer, Charles A Brown, Juan Mondragon, David E Persse, Manish I Shah

West J Emerg Med 2019 Oct 21;20(6):962-969 

Abstract

Introduction: Prehospital pediatric endotracheal intubation has lower first-pass success rates compared to adult intubations and in general may not offer a survival benefit. Increasingly, emergency medical services (EMS) systems are deploying prehospital extraglottic airways (EGA) for primary pediatric airway management, yet little is known about their efficacy. We evaluated the impact of a pediatric prehospital airway management protocol change, inclusive of EGAs, on airway management and patient outcomes in children in cardiac arrest or respiratory failure.

Methods: Using data from a large, metropolitan, fire-based EMS service, we performed an observational study of pediatric patients with respiratory failure or cardiac arrest who were transported by EMS before and after implementation of an evidence-based airway management protocol inclusive of the addition of the EGA. The primary outcome was change in frequency of intubation attempts when paired with an initial EGA. Secondary outcomes included EGA and intubation success rates and patient survival to hospitalization and discharge.

Results: We included 265 patients age <16 years old, with 142 pre- and 123 post-protocol change. Patient demographics and event characteristics were similar between groups.

Intubation attempts declined from 79.6% pre- to 44.7% (p<0.01) post-protocol change. In patients with an intubation attempt, overall intubation success declined from 81.4% to 63.6% (p<0.01). Post-protocol change, an EGA was attempted in 52.8% of patients with 95.4% success.

Conclusion: Implementation of an evidenced-based airway management algorithm for pediatric patients, inclusive of an EGA device for all age groups, was associated with fewer prehospital intubations. Intubation success may be negatively impacted due to decreases in procedural frequency.

Prehospital care of burn injuries in Africa: A review, 1990-2018

Anne H Outwater, Tanya Van Braekel

Burns 2019 Nov 27;S0305-4179(19)30173-1

Purpose: Administration of appropriate first aid immediately after a burn injury is crucial to averting further harm to the victim, physically and psychologically. The aim of this review is to enable the design of better interventions by describing what is known about prehospital care of burn victims in Africa.

Results: This review is based on 17 articles from 5 countries. For the purposes of the review, first responders are defined as those nearest the victim when a burn occurs. First responders include nonclinicians, most typically the mother of a young burn victim. Forty-five different substances, sometimes used in combination, are reported to have been applied to burn injuries: water, 15 food items (especially oils and egg), 14 pharmaceutical products, 9 traditional treatments, 5 minerals (petroleum products being the most common), and charcoal. Appropriate treatment, defined as the application of cool water for 10 min, was achieved about 0.5% of the time, most frequently in Cape Town, South Africa. Most victims do not have their wounds covered while they are transported to a health-care facility. Treatment delays are common. Pain management is hardly addressed.

Conclusions: Appropriate prehospital care for burn injury generally is not practiced in Africa. Yet best practices for prehospital care are affordable, available, and easily understood. The greatest risk factor for poor care is first responders' lack of knowledge. Awareness and education campaigns focusing on the lay public, as well as educational institutions for health workers, are urgently needed throughout the continent.

Advanced airway management success rates in a national cohort of emergency medical services agencies

Tracy Nwanne, Jeffrey Jarvis, Dustin Barton, John P Donnelly, Henry E Wang 

Resuscitation. 2020 Jan 1;146:43-49 

Objective: Despite its important role in care of the critically ill, there have been few large-scale descriptions of the epidemiology of Emergency Medical Services (EMS) advanced airway management (AAM) and the variations in care with different patient subsets. We sought to characterize AAM performance in a national cohort of EMS agencies. 

Methods: We used data from ESO Solutions, Inc., a national EMS electronic health record system. We analyzed EMS emergency patient encounters during 2011-2015 with attempted AAM. We categorized AAM techniques as conventional endotracheal intubation (cETI), neuromuscular blockade assisted intubation (NMBA-ETI), supraglottic airway (SGA), and cricothyroidotomy (needle and open). Determination of successful AAM was based on EMS provider report. We analyzed the data using descriptive statistics, determining the incidence and clinical characteristics of AAM cases. We determined success rates for each AAM technique, stratifying by the subsets cardiac arrest, medical non-arrest, trauma, and pediatrics (age ≤12 years). 

Results: AAM occurred in 57,209 patients. Overall AAM success was 89.1% (95% CI: 88.8-89.3%) across all patients and techniques. Intubation success rates varied by technique; cETI (n = 38,004; 76.9%, 95% CI: 76.5-77.3%), NMBA-ETI (n = 6768; 89.7%, 88.9-90.4%). SGAs were used both for initial (n = 9461, 90.1% success, 95% CI: 89.5-90.7%) and rescue (n = 5994, 87.3% success, 95% CI: 86.4-88.1%) AAM. Cricothyroidotomy success rates were low: initial cricothyroidotomy (n = 202, 17.3% success, 95% CI: 12.4-23.3%), rescue cricothyroidotomy (n = 85, 52.9% success, 95% CI: 41.8-88%). AAM success rates varied by patient subset: cardiac arrest (n = 35,782; 91.7%, 95% CI: 91.4-92.0), medical non-arrest (n = 17,086; 84.7%, 84.2-85.2%); trauma (n = 4341; 84.3%, 83.1-85.3%); pediatric (n = 1223; 73.7%, 71.2-76.2%). 

Conclusion: AAM success rates varied by airway technique and patient subset. In this national cohort, these results offer perspectives of EMS AAM practices.

Paramedic Pain Management Practice with Introduction of a Non-opiate Treatment Protocol

 Laurel O'Connor, Julianne Dugas, Jeffrey Brady, Andrew Kamilaris, Steven K Shiba, Ricky C Kue, John P Broach 

West J Emerg Med. 2020 Aug 21;21(5):1234-1241 

Introduction: There is concern about the initiation of opiates in healthcare settings due to the risk of future misuse. Although opiate medications have historically been at the core of prehospital pain management, several states are introducing non-opiate alternatives to prehospital care. Prior studies suggest that non-opiate analgesics are non-inferior to opiates for many acute complaints, yet there is little literature describing practice patterns of pain management in prehospital care. Our goal was to describe the practice patterns and attitudes of paramedics toward pain management after the introduction of non-opiates to a statewide protocol. 

Methods: This study was two-armed. The first arm employed a pre/post retrospective chart review model examining medication administrations reported to the Massachusetts Ambulance Trip Information System between January 1, 2017-December 31, 2018. We abstracted instances of opiate and non-opiate utilizations along with patients' clinical course. The second arm consisted of a survey administered to paramedics one year after implementation of non-opiates in the state protocol, which used binary questions and Likert scales to describe beliefs pertaining to prehospital analgesia. 

Results: Pain medications were administered in 1.6% of emergency medical services incidents in 2017 and 1.7% of incidents in 2018. The rate of opiate analgesic use was reduced by 9.4% in 2018 compared to 2017 (90.6% vs 100.0%). The absolute reduction in opiate use in 2018 was 3.6%. Women were less likely (odds ratio [OR] = 0.78, 95% confidence interval [CI], 0.69-0.89) and trauma patients were more likely to receive opiates (OR = 2.36, CI, 1.96-2.84). Mean transport times were longer in opiate administration incidents (36.97 vs 29.35 minutes, t = 17.34, p<0.0001). We surveyed 100 paramedics (mean age 41.98, 84% male). Compositely, 85% of paramedics planned to use non-opiates and 35% reported having done so. Participants planning to use non-opiates were younger and less experienced. Participants indicated that concern about adverse effects, efficacy, and time to effect impacted their practice patterns. 

Conclusion: The introduction of non-opiate pain medication to state protocols led to reduced opiate administration. Men and trauma patients were more likely to receive opiates. Paramedics reported enthusiasm for non-opiate medications. Beliefs about non-opioid analgesics pertaining to adverse effects, onset time, and efficacy may influence their utilization.

Comparing I-Gel to Proseal Laryngeal Mask Airways in Infants: A Prospective Randomised Clinical Study

Sibel Oba, Hacer Şebnem Türk, Leyla Kılınç, Birsen Ekşioğlu Karacı, Serkan İslamoğlu 

Turk J Anaesthesiol Reanim. 2020 Aug;48(4):308-313 

Objective: Laryngeal mask airways and the I-gel have become increasingly popular for children undergoing minor surgery. The goal of our study is to compare I-gel and ProSeal laryngeal mask airways (LMA) in infants by analysing different parameters, such as insertion success, ventilation, haemodynamic changes and postoperative complications. 

Methods: For this prospective, randomised study, we selected 123 infants with an American Society of Anaesthesiologists (ASA) status I, who were undergoing minor elective lower abdominal surgery. After obtaining verbal and written informed consent from the parents, the infants were divided into two groups: the I-gel group (n=60) and the ProSeal LMA group (n=63). The times and ease of insertion, percentages of tidal volume leakage, and means and leakage pressures of these two supraglottic airways were noted. The complications and side-effects of each method were also recorded. 

Results: The insertion time of the ProSeal group was statistically shorter than that of the I-gel group. The peak and mean pressures and the leakage percentage of the ProSeal group were statistically lower than those of the I-gel group. The leakage pressure of the ProSeal group was statistically higher than the I-gel group. 

Conclusion: In comparison with I-gel, the use of ProSeal LMA in infants' anaesthesia presents many advantages, such as the ease of its insertion, better oropharyngeal leakage pressure and less mucosal hyperaemia.

Prehospital treatment of burns in Tanzania: a mini-meta-analysis

Anne H Outwater, Abel Thobias, Peter M Shirima, Notikela Nyamle, Greyson Mtavangu, Mwanahawa Ismail, Lusajo Bujile, Mary Justin-Temu

Int J Burns Trauma 2018 Jun 20;8(3):68-76 

Abstract

The present study describes initial burn injury care in Tanzania-materials applied, sources of information, reasons for applying the materials, and time to a health centre-in order to suggest ways to optimize initial care. Eight small studies were conducted in which burn-injured patients were interviewed who had been admitted to referral hospitals in four regions in Tanzania. Most burn injuries in Tanzania occur in the home cooking area, and it was found that the first responders were family members, friends, and neighbours. A total of 710 burn victims were interviewed. Twenty-four different materials were applied to the patients' wounds. The most common application was honey. Only 14.3% of the victims received the recommended form of care: application of cool water. It was also found that nothing was applied to the wounds of 17.5% of these patients by first responders. Sources of information on burn treatment were family, friends and neighbours, and, less often, health workers or the media. Most of the burn victims' households had enough water to enable administration of recommended initial care.

The main impediment to the provision of appropriate initial treatment of a burn appears to be lack of correct and useful knowledge about what to do immediately after the injury. A two- pronged educational approach should be used to improve care. A national mass media campaign should start immediately to inform ordinary citizens about proper initial treatment of burns. In addition, curricula of all schools that train health workers need to be reviewed for accuracy, and appropriate knowledge about initial care of burn victims should be added if necessary. Measures to improve burn first aid, are relatively easy, even in a low-income country such as Tanzania.

Prehospital care of burn injuries in Africa: A review, 1990-2018

Anne H Outwater, Tanya Van Braekel

Burns 2019 Nov 27;S0305-4179(19)30173-1 

Abstract

Purpose: Administration of appropriate first aid immediately after a burn injury is crucial to averting further harm to the victim, physically and psychologically. The aim of this review is to enable the design of better interventions by describing what is known about prehospital care of burn victims in Africa.

Results: This review is based on 17 articles from 5 countries. For the purposes of the review, first responders are defined as those nearest the victim when a burn occurs. First responders include nonclinicians, most typically the mother of a young burn victim. Forty-five different substances, sometimes used in combination, are reported to have been applied to burn injuries: water, 15 food items (especially oils and egg), 14 pharmaceutical products, 9 traditional treatments, 5 minerals (petroleum products being the most common), and charcoal. Appropriate treatment, defined as the application of cool water for 10 min, was achieved about 0.5% of the time, most frequently in Cape Town, South Africa. Most victims do not have their wounds covered while they are transported to a health-care facility. Treatment delays are common. Pain management is hardly addressed.

Conclusions: Appropriate prehospital care for burn injury generally is not practiced in Africa. Yet best practices for prehospital care are affordable, available, and easily understood. The greatest risk factor for poor care is first responders' lack of knowledge. Awareness and education campaigns focusing on the lay public, as well as educational institutions for health workers, are urgently needed throughout the continent.

Successful endotracheal intubation using i-gel supraglottic airway device and ultrasonography in a patient with bedside cervical traction: A case report

Sin Ryul Park, Won Joon Jeong 

J Clin Ultrasound. 2021 Mar;49(3):290-292 

Abstract 

We report a case of successful endotracheal intubation using i-gel and ultrasonography without a laryngoscope in a patient with a bedside cervical traction device. A 57-year-old man was referred to the emergency department because of quadriparesis following a motor vehicle accident, who was confirmed to have cervical dislocation with spinal cord compression. For ventilation support, the i-gel rescue airway device was placed to secure the patient airway temporarily. Then, an endotracheal tube was passed through the stem of the i-gel while observing the optimal tube position with ultrasonography. This case showed that ultrasonography can be used for early confirmation of endotracheal tube placement into the trachea via the i-gel.

Critical events during intra-hospital transport of critically ill patients to and from intensive care unit

Mohd Qurram Parveez, Lakshmi Narayana Yaddanapudi, Vikas Saini, Kamal Kajal, Ankur Sharma

Turk J Emerg Med. 2020 Jul 18;20(3):135-141 

Objectives: Intensive care unit (ICU) patients are at an increased risk of many catastrophic events during intrahospital transport (IHT) for various procedures. This study was planned to determine the incidence and types of adverse events occurring during the transport of critically ill patients in a tertiary care hospital. 

Methods: This prospective observational study was conducted in the ICU of a tertiary care hospital for 8 months after ethical clearance from the institute ethics committee. All patients transported out of the ICU during the audit period for diagnostic or therapeutic procedures were included in the study. Vitals and several study parameters were recorded before, during, and after shifting patients to and from the ICU. Various critical events were noted during transport and classified into major and minor critical events based on the presence and absence of potential consequences that lead to a change of therapy during transport. 

Results: One hundred and sixty patients were studied for consecutive IHT to and from the ICU. The patients were transported for imaging studies (58.1%), minor surgery (31.8%), major surgery (2.5%), and other procedures (7.5%). A total of 248 critical events were observed in 104 IHTs (65%; 95% confidence interval [95% CI]: 57.4%-72.1%). Hence, an average of 2.38 critical events occurred per IHT. There were 31 major events among the 248 critical events (12.5%; 95% CI: 8.8%-17.1%). 

Conclusions: Standard guidelines about the accompanying personnel and monitoring need to be followed during IHT. Conduct of minor surgical procedures in the ICU and better bedside diagnostic procedures may be considered for the future.

Efficacy and safety of kaolin-based hemostatic pad vs. standard mechanical compression following transradial and transulnar access for elective coronary angiography and PCI: RAUL trial substudy

Lewandowski Pawel, Gralak-Lachowska Dagmara, Maciejewski Pawel, Ramotowski Bogumil, Budaj Andrzej, Stec Sebastian

Heart Vessels 2020 Apr;35(4):502-508 

Abstract 

Hemostatic devices used in the transradial approach (TRA) and transulnar approach (TUA) are limited. This study compared the efficacy and safety of hemostasis using the QuikClot Radial hemostatic pad (QC) vs. standard mechanical compression (SC) after coronary angiography (CAG). This prospective single-center randomized trial included CAG patients. The primary and secondary endpoints were efficacy (successful hemostasis) and safety (total artery occlusion [TAO], pseudoaneurysm, hematoma), respectively. A visual analog scale (VAS) evaluated patient pain during compression. In 2013-2017, 200 patients were randomized 2 × 2 into the: (1) TRA and TUA groups and (2) QC and SC groups. Successful hemostasis was achieved in 92 (92%) patients in the QC group and 100 (100%) patients in the SC group (p < 0.006). The TRA SC subgroup showed significantly better results than the TRA QC subgroup (100% vs. 90.0%; p< 0.03). Similar results were obtained in the TUA QC and TUA SC subgroups (95% vs. 100%; p= 0.5). The secondary endpoint was achieved in the QC and SC groups (8% vs. 9%; p = 0.8). Patients reported significantly less pain during QC application than during SC (VAS: 2.6 ± 2.6 vs. 3.4 ± 2.9; p < 0.03). In patients undergoing CAG with TRA or TUA, QC was associated with lower efficacy, less discomfort, and similar safety compared to SC.

A New Insight into Meloxicam: Assessment of Antioxidant and Anti-Glycating Activity in In Vitro Studies

Cezary Pawlukianiec, Małgorzata Ewa Gryciuk, Kacper Maksymilian Mil, Małgorzata Żendzian-Piotrowska, Anna Zalewska, Mateusz Maciejczyk

Pharmaceuticals (Basel). 2020 Sep 10;13(9):240

Abstract 

Meloxicam is a non-steroidal anti-inflammatory drug, which has a preferential inhibitory effect to cyclooxyganase-2 (COX-2). Although the drug inhibits prostaglandin synthesis, the exact mechanism of meloxicam is still unknown. This is the first study to assess the effect of meloxicam on protein glyco-oxidation as well as antioxidant activity. For this purpose, we used an in vitro model of oxidized bovine serum albumin (BSA). Glucose, fructose, ribose, glyoxal and methylglyoxal were used as glycating agents, while chloramine T was used as an oxidant. We evaluated the antioxidant properties of albumin (2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity, total antioxidant capacity and ferric reducing antioxidant power), the intensity of protein glycation (Amadori products, advanced glycation end products) and glyco-oxidation (dityrosine, kynurenine, N-formylkynurenine, tryptophan and amyloid-β) as well as the content of protein oxidation products (advanced oxidation protein products, carbonyl groups and thiol groups). We have demonstrated that meloxicam enhances the antioxidant properties of albumin and prevents the protein oxidation and glycation under the influence of various factors such as sugars, aldehydes and oxidants. Importantly, the antioxidant and anti-glycating activity is similar to that of routinely used antioxidants such as captopril, Trolox, reduced glutathione and lipoic acid as well as protein glycation inhibitors (aminoguanidine). Pleiotropic action of meloxicam may increase the effectiveness of anti-inflammatory treatment in diseases with oxidative stress etiology.

Analysis of U.S. Pacific Command Area of Operations Military Medical Transportations of Adult Patients, 2008 to 2018

Alec J Pawlukiewicz, Rachel E Bridwell, Brandon M Carius, Steven G Schauer, Joseph K Maddry, William T Davis 

Mil Med. 2020 Nov 21;usaa289. doi: 10.1093/milmed/usaa289. Online ahead of print. 

Introduction: With more than 370,000 military and civilian personnel stationed across Pacific Command (PACOM), medical evacuation in this largest command presents unique challenges. The authors describe medical evacuations analyzed from the U.S. Air Force Transportation Command Regulating and Command & Control Evacuation System (TRAC2ES) in PACOM. 

Materials and methods: We performed a retrospective review of all TRAC2ES medical records for medical evacuations of adult patients from the PACOM theater of operations conducted between January 1, 2008 and December 31, 2018. We abstracted free text data entry in TRAC2ES to characterize the diagnoses requiring patient movement. Data are presented using descriptive statistics. 

Results: During this 11-year period, 3,328 PACOM TRAC2ES encounters met inclusion criteria. Of these evacuations, 65.8% were male and were comprised mostly of active duty military (1,600, 48.1%) and U.S. civilians (1,706, 51.3%). Most transports originated in Japan (1,210 transports, 36.4%) or Guam (924 transports, 27.8%) with Hawaii (1,278 transports, 38.4%) as the most frequent destination. The majority of evacuations were routine (72.5%) with only 4.9% urgent evacuations. Medical conditions (2,905 transports, 87%) accounted for the largest proportion of transports, surpassing injuries (442 transports, 13%). The most common reasons for medical transports were behavioral health (671 transports, 20.2%) and cardiovascular disease (505 transports, 15.1%). 

Conclusions: The majority of medical evacuations in PACOM were because of medical illness with routine precedence category, mirroring the largely noncombat operations occurring across this large area.

2020 American Heart Association and American Red Cross Focused Update for First Aid

Jeffrey L Pellegrino, Nathan P Charlton, Jestin N Carlson, Gustavo E Flores, Craig A Goolsby, Amber V Hoover, Amy Kule, David J Magid, Aaron M Orkin, Eunice M Singletary, Tammy M Slater, Janel M Swain 

Circulation. 2020 Oct 27;142(17):e287-e303 

No abstract available

 

"Stop the Bleed" Education Assessment Tool (SBEAT): Development and Validation

Jeffrey L Pellegrino 1, Nathan Charlton 2, Craig Goolsby 3 4

Cureus. 2020 Sep 21;12(9):e10567. doi: 10.7759/cureus.10567

Abstract 

As part of the national Stop the Bleed campaign in the United States, more than a million people have received bleeding control training through the work of many organizations. These public and professional educational experiences are ideally grounded in health sciences, clinical, and educational evidence to be most effective. However, there is currently no standard tool for evaluating the educational quality of these programs. We developed and validated the Stop the Bleed Education Assessment Tool (SBEAT) to provide a standard measure of life-threatening bleeding educational programs knowledge learning outcomes to aid in evaluation and development of this public health program. The SBEAT development included medical, clinical, and educational experts to derive and validate learning outcomes. Specific item writing incorporated focus groups for input on language and then pilot testing before a full community pilot test established a data set, for which a Rasch methodology was applied. The resulting tool used 34 items embedded in 19 survey questions, with item separation statistic of 5.56 (0.97 reliability) and person separation statistic of 2.09 (0.81 reliability) for 171 persons. Overall, the Cronbach Alpha (KR-20) person score "test reliability" equaled 0.85 (SEM = 2.24). The SBEAT project establishes a standardized assessment tool to evaluate the cognitive aspects of first aid for life threatening bleeding. Comparison of outcomes from different teaching styles and methods will allow for the development of best practices for future bleeding control education and help organizations demonstrate value to learners, funders, and policy makers, and advance health sciences education. SBEAT offers a measure for which educational efficiency and efficacy can be judged within a larger effort to prepare people for personal emergencies or large-scale disasters.

Triaged Treatment-Based Conventional Weapon Combat Wound Classification Code Design and Injury Spectrum Statistical Analysis

Bo Peng, Shuo Liu, Lei Xu, Zhen He 

Mil Med. 2020 Dec 30;185(11-12):e2032-e2038 

Introduction: We create an expandable combat wound classification coding system and a stratified standardized combat wound injury spectrum to support triage according to the treatment echelon and to provide the basis for the rapid and efficient classification of combat casualties. The coding system simultaneously assists in identifying injuries with a high incidence of fatality that require emergency treatment, and provides a framework for the triage of combat wounds in mass casualty situations. 

Materials and methods: The three-tiered treatment echelon consisting of battlefield on-site first aid, emergency treatment, and early treatment was used to design an expanded combat wound classification coding system according to the differential needs of combat wound treatment. The Herfindahl-Hirschman Index (HHI) index was used as the key indicator for injury spectrum ranking and was applied to select the key anatomical structures that require the highest priority treatment in the three treatment echelons. The combat wound classification codes were based on the results of consultations with selected experts and results from the HHI index calculations. The use of the classification codes at the battlefield on-site first aid stage and emergency treatment stage was evaluated in exercises to test and compare the effectiveness of the classification codes against current classification systems. 

Results: We obtained exhaustive combinations from the vast number of combat wound factors in combat wound classification codes, constructed injury spectrum frameworks within the different treatment echelons, and identified injuries with a high-incidence of fatality in each of the treatment echelons. Compared with traditional methods, the time spent on coding was reduced and classification accuracy was improved when using the new classification codes, which led to improved efficiency of classification and a reduced workload for hospital staff. 

Conclusions: The combat wound classification codes that were established through the HHI index and expert consultations achieved good results in terms of having higher classification speed and accuracy than traditional methods. This means they could be used to identify injuries with a high-incidence of fatality and provide guidance to improve the efficiency of treatment among all treatment echelons in the army.

Hemostatic agents for prehospital hemorrhage control: a narrative review

Henry T Peng

Mil Med Res 2020 Mar 25;7(1):13 

Hemorrhage is the leading cause of preventable death in combat trauma and the secondary cause of death in civilian trauma. A significant number of deaths due to hemorrhage occur before and in the first hour after hospital arrival. A literature search was performed through PubMed, Scopus, and Institute of Scientific Information databases for English language articles using terms relating to hemostatic agents, prehospital, battlefield or combat dressings, and prehospital hemostatic resuscitation, followed by cross-reference searching. Abstracts were screened to determine relevance and whether appropriate further review of the original articles was warranted. Based on these findings, this paper provides a review of a variety of hemostatic agents ranging from clinically approved products for human use to newly developed concepts with great potential for use in prehospital settings. These hemostatic agents can be administered either systemically or locally to stop bleeding through different mechanisms of action. Comparisons of current hemostatic products and further directions for prehospital hemorrhage control are also discussed.

A Telemedicine Case Series for Acute Medical Emergencies in Greenland: A Model for Austere Environments

Luit Penninga, Anne Kathrine Lorentzen, Christopher Davis Telemed

J E Health 2019 Dec 4. Online ahead of print.

Abstract

Background: Greenland is a vast country, with immense geographical distances and often extreme weather conditions. Specialized health care is limited to larger cities, and qualified medical care is not always immediately available in rural areas. Telemedicine infrastructure is available throughout the country.

Purpose: The purpose of this study was to identify the role of telemedicine in the diagnosis and treatment of acute medical emergencies in remote settlements. Materials and Methods: All medical emergencies were screened from 2015 to 2016 in remote settlements of the Avannaa Health Region in Northwest Greenland, and cases in which telemedicine was utilized were identified.

Results: Three illustrative cases were identified. Diagnoses were severe asthma, bilateral pneumonia, and heart failure. All three patients were accurately diagnosed through a telemedical consultation, and early treatment was initiated. In two out of three patients, acute medical evacuation by air ambulance was avoided, and the third patient was stabilized by the time an air ambulance arrived.

Conclusions: Telemedicine allows for the accurate diagnosis of acute medical emergencies in remote settlements of Greenland and facilitates timely initiation of treatment. This may reduce morbidity and mortality of acute medical illness. In addition, telemedicine may aid in the clinical decision-making on whether or not to arrange for medical evacuation. Avoiding unnecessary medical evacuations reduces cost and risk to air ambulance crews. In addition, telemedicine allows for close monitoring of the patient until the air ambulance arrives. Telemedicine also ensures diagnostic and treatment options when medical evacuation is impossible due to extreme weather conditions. From a global perspective, telemedicine may increase the availability and quality of health care in remote areas and reduce health inequalities between remote and urban areas.

Characteristics and Impact of U.S. Military Blast-Related Mild Traumatic Brain Injury: A Systematic Review

Helen Phipps, Stefania Mondello, Arlington Wilson, Travis Dittmer, Natalie N Rohde, Paul J Schroeder, Jaime Nichols, Camille McGirt, Justin Hoffman, Kaila Tanksley, Mariam Chohan, Amanda Heiderman, Hussein Abou Abbass, Firas Kobeissy6, Sidney Hinds

Front Neurol. 2020 Nov 2;11:559318. doi: 10.3389/fneur.2020.559318. eCollection 2020

Abstract 

As a result of armed conflict, head trauma from exposure to blasts is an increasing critical health issue, particularly among military service members. Whilst numerous studies examined the burden of blast-related brain injuries on service members', few systematic reviews have been published. This work provides a comprehensive summary of the evidence on blast-related mild traumatic brain injury (mTBI) burden in active U.S. military service members and inactive Veterans, describing characteristics and outcomes. Records published up to April 2017 were identified through a search of PubMed, Web of Science, Scopus, Ovid MEDLINE, and Cochrane Library. Records-based and original research reporting on U.S. military service members and Veterans with mild blast TBI were included. Data on subject characteristics, exposure, diagnostic criterion, and outcomes were extracted from included studies using a standardized extraction form and were presented narratively. Of the 2,290 references identified by the search, 106 studies with a total of 37,515 participants met inclusion criteria for blast-related mTBI. All but nine studies were based out of military or Veteran medical facilities. Unsurprisingly, men were over-represented (75-100%). The criteria used to define blast-related mTBI were consistent; however, the methodology used to ascertain whether individuals met those criteria for diagnosis were inconsistent. The diagnosis, most prevalent among the Army, heavily relied on self-reported histories. Commonly reported adverse outcomes included hearing disturbances and headaches. The most frequently associated comorbidities were post-traumatic stress disorder, depression, anxiety, sleep disorders, attention disorders, and cognitive disorders. The primary objective of this review was to provide a summary of descriptive data on blast-related mTBI in a U.S. military population. Low standardization of the methods for reaching diagnosis and problems in the study reporting emphasize the importance to collect high-quality data to fill knowledge gaps pertaining to blast-related mTBI.

Efficacy of warming systems in mountain rescue: an experimental manikin study

Paweł Podsiadło, Ewa Zender-Świercz, Giacomo Strapazzon, Sylweriusz Kosiński, Marek Telejko, Tomasz Darocha, Hermann Brugger 

Int J Biometeorol. 2020 Dec;64(12):2161-2169

Abstract 

Mountain accident casualties are often exposed to cold and windy weather. This may induce post-traumatic hypothermia which increases mortality. The aim of this study was to assess the ability of warming systems to compensate for the victim's estimated heat loss in a simulated mountain rescue operation. We used thermal manikins and developed a thermodynamic model of a virtual patient. Manikins were placed on a mountain rescue stretcher and exposed to wind chill indices of 0 °C and - 20 °C in a climatic chamber. We calculated the heat balance for two simulated clinical scenarios with both a shivering and non-shivering victim and measured the heat gain from gel, electrical, and chemical warming systems for 3.5 h. The heat balance in the simulated shivering patient was positive. In the non-shivering patient, we found a negative heat balance for both simulated weather conditions (- 429.53 kJ at 0 °C and - 1469.78 kJ at - 20 °C). Each warming system delivered about 300 kJ. The efficacy of the gel and electrical systems was higher within the first hour than later (p < 0.001). We conclude that none of the tested warming systems is able to compensate for heat loss in a simulated model of a non-shivering patient whose physiological heat production is impaired during a prolonged mountain evacuation. Additional thermal insulation seems to be required in these settings.

An up-to-date overview of sublingual sufentanil for the treatment of moderate to severe pain

Susanna Porela-Tiihonen, Hannu Kokki, Merja Kokki

Expert Opin Pharmacother. 2020 Aug;21(12):1407-1418

Introduction: Sufentanil is a selective µ-opioid agonist, used intravenously and intrathecally for moderate to severe acute pain. Sublingual sufentanil nanotablets have been developed; 15 mcg tablet for a patient-controlled analgesia device and 30-mcg tablet for a single-dose device administered by a healthcare professional. Dosing interval is a minimum of 20 min for a 15 mcg tablet and a treatment duration of up to 72 hours. The single 30-mcg nanotablet dosing interval is 1 hour. Mean plasma elimination half-life is 13 hours and bioavailability 47-57% after the first sublingual sufentanil tablet.

Areas covered: This review focuses on the effectiveness, safety, and feasibility of sublingual sufentanil 30-mcg single dose suspended by a healthcare professional for the management of moderate to severe acute pain. A few Phase 4 studies concerning the sublingual sufentanil tablet system containing 15-mcg nanotablets are also reviewed.

Expert opinion: Sufentanil sublingual 30-mcg nanotablets provide effective pain relief in various acute moderate to severe pain states. The safety profile of sublingual sufentanil 30 mcg is typical to opioids nausea, vomiting, and sedation being the most common ones. Sublingual sufentanil 30-mcg nanotablet has the potential for efficient moderate to severe pain management in supervised healthcare facilities.

Predictors of Definitive Airway Sans Hypoxia/Hypotension on First Attempt (DASH-1A) Success in Traumatically Injured Patients Undergoing Prehospital Intubation

Prehosp Emerg Care Jul-Aug 2020;24(4):470-477

Elizabeth K Powell, William R Hinckley, Uwe Stolz, Andrew J Golden, Amanda Ventura, Jason T McMullan 

Abstract

Background: Prehospital intubation success is routinely treated as a dichotomous outcome based on an endotracheal tube passing through vocal cords regardless of number of attempts or occurrence of hypoxia, or hypotension, which are associated with worse outcomes. We explore patient, provider, and procedure-related variables associated with successful definitive airway sans hypoxia/hypotension on first attempt (DASH-1A) in traumatically injured subjects undergoing endotracheal intubation at the scene of injury by a helicopter EMS system.

Methods: This single-center retrospective chart review included patients with traumatic injuries and at least one attempted intubation by helicopter EMS at the scene of injury. Demographic and clinical variables were tested for association with DASH-1A and overall first-attempt success using univariate comparisons and multivariable logistic regression to produce adjusted odds ratios (aORs) and 95% confidence intervals (CIs). Purposeful backwards stepwise elimination was used to develop logistic regression models for outcomes. Initial inclusion of covariates in multivariable models was based on clinical judgement, known or suspected risk factors and confounders for intubation success, and univariate associations.

Results: Of 419 subjects screened, 263 met inclusion criteria. Median age was 34 years and the majority of subjects were Caucasian (95%), male (76%), and suffered blunt trauma (90%). The endotracheal tube was successfully placed on the first attempt in 198 (75.3%) of patients, but only 142 (55.3%) had a successful DASH-1A, and overall, 246 (94%) had an endotracheal tube passed successfully before hospital arrival. Factors significantly associated with successful DASH-1A were no ground EMS intubation attempt prior to arrival [aOR 2.2 (CI 1.0-4.9)], lack of airway secretions/blood [1.9 (1.0-3.4)], Cormack-Lehane Score of I and II [12.3 (4.5-33.2) & 3.2 (1.2-9.1), respectively], and bougie use [5.4 (1.8-15.8)]. For endotracheal tube passing only, the following were significantly associated with first pass success: grade of view I and II [aORs 87.3 (CI 25.8-295.7) & 6.8 (2.3-19.5), respectively], lack of secretions/blood [4.9 (2.1-11.2), bougie use [7.8 (2.3-26.3)], direct laryngoscopy [5.1 (1.5-17.0)] and not using apneic oxygenation through a nasal cannula [2.5 (1.1-5.6)].Conclusion: In our helicopter EMS system, successful endotracheal intubation on the first attempt and without an episode of hypoxia was associated with no ground EMS intubation attempt prior to flight crew arrival, lack of airway secretions/blood, Cormack-Lehane Score, and bougie use.

End-tidal and arterial carbon dioxide gradient in serious traumatic brain injury after prehospital emergency anaesthesia: a retrospective observational study

James Price, Daniel D Sandbach, Ari Ercole, Alastair Wilson, Ed Benjamin Graham Barnard 

Emerg Med J. 2020 Nov;37(11):674-679 

Objectives: In the UK, 20% of patients with severe traumatic brain injury (TBI) receive prehospital emergency anaesthesia (PHEA). Current guidance recommends an end-tidal carbon dioxide (ETCO2) of 4.0-4.5 kPa (30.0-33.8 mm Hg) to achieve a low-normal arterial partial pressure of CO2 (PaCO2), and reduce secondary brain injury. This recommendation assumes a 0.5 kPa (3.8 mm Hg) ETCO2-PaCO2 gradient. However, the gradient in the acute phase of TBI is unknown. The primary aim was to report the ETCO2-PaCO2 gradient of TBI patients at hospital arrival. 

Methods: A retrospective cohort study of adult patients with serious TBI, who received a PHEA by a prehospital critical care team in the East of England between 1 April 2015 and 31 December 2017. Linear regression was performed to test for correlation and reported as R-squared (R2). A Bland-Altman plot was used to test for paired ETCO2 and PaCO2 agreement and reported with 95% CI. ETCO2-PaCO2 gradient data were compared with a two-tailed, unpaired, t-test. 

Results: 107 patients were eligible for inclusion. Sixty-seven patients did not receive a PaCO2 sample within 30 min of hospital arrival and were therefore excluded. Forty patients had complete data and were included in the final analysis; per protocol. The mean ETCO2-PaCO2 gradient was 1.7 (±1.0) kPa (12.8 mm Hg), with moderate correlation (R2=0.23, p=0.002). The Bland-Altman bias was 1.7 (95% CI 1.4 to 2.0) kPa with upper and lower limits of agreement of 3.6 (95% CI 3.0 to 4.1) kPa and -0.2 (95% CI -0.8 to 0.3) kPa, respectively. There was no evidence of a larger gradient in more severe TBI (p=0.29). There was no significant gradient correlation in patients with a coexisting serious thoracic injury (R2=0.13, p=0.10), and this cohort had a larger ETCO2-PaCO2 gradient, 2.0 (±1.1) kPa (15.1 mm Hg), p=0.01. Patients who underwent prehospital arterial blood sampling had an arrival PaCO2 of 4.7 (±0.2) kPa (35.1 mm Hg). 

Conclusion: There is only moderate correlation of ETCO2 and PaCO2 at hospital arrival in patients with serious TBI. The mean ETCO2-PaCO2 gradient was 1.7 (±1.0) kPa (12.8 mm Hg). Lower ETCO2 targets than previously recommended may be safe and appropriate, and there may be a role for prehospital PaCO2 measurement.

Expired But Not Yet Dead: Examining the Red Blood Cell Storage Lesion in Extended-Storage Whole Blood

Kasiemobi E Pulliam, Bernadin Joseph, Rosalie A Veile, Lou Ann Friend, Amy T Makley, Charles C Caldwell, Alex B Lentsch, Michael D Goodman, Timothy A Pritts 

Shock. 2021 Apr 1;55(4):526-535 

Abstract 

Whole blood is a powerful resuscitation strategy for trauma patients but has a shorter shelf life than other blood products. The red blood cell storage lesion in whole blood has not previously been investigated beyond the standard storage period. In the present study, we hypothesized that erythrocytes in stored whole blood exhibit similar aspects of the red blood cell storage lesion and that transfusion of extended storage whole blood would not result in a more severe inflammatory response after hemorrhage in a murine model. To test this hypothesis, we stored low-titer, O-positive, whole blood units, and packed red blood cells (pRBCs) for up to 42 days, then determined aspects of the red blood cell storage lesion. Compared with standard storage pRBCs, whole blood demonstrated decreased microvesicle and free hemoglobin at 21 days of storage and no differences in osmotic fragility. At 42 days of storage, rotational thromboelastometry demonstrated that clotting time was decreased, alpha angle was increased, and clot formation time and maximum clot firmness similar in whole blood as compared with pRBCs with the addition of fresh frozen plasma. In a murine model, extended storage whole blood demonstrated decreased microvesicle formation, phosphatidylserine, and cell-free hemoglobin. After hemorrhage and resuscitation, TNF-a, IL-6, and IL-10 were decreased in mice resuscitated with whole blood. Red blood cell survival was similar at 24 h after transfusion. Taken together, these data suggest that red blood cells within whole blood stored for an extended period of time demonstrate similar or reduced accumulation of the red blood cell storage lesion as compared with pRBCs. Further examination of extended-storage whole blood is warranted.

Efficacy of a Temporary Hemostatic Device in a Swine Model of Closed, Lethal Liver Injury

Hao Qin, Lei Yang, Daocheng Liu, Sixu Chen, Mingrui Lyu, Quanwei Bao, Xinan Lai  Huayu Liu, Qiang Chen, Zhaowen Zong 

Mil Med. 2020 Jun 8;185(5-6):e742-e747 

Introduction: Solid abdominal organ hemorrhage remains one of the leading causes of death both on the battlefield of modern warfare and in the civilian setting. A novel, temporary hemostatic device combining CELOX and direct intra-abdominal physical compression was invented to control closed SAOH during transport to a medical treatment facility. 

Materials and methods: A swine model of closed, lethal liver injury was established to determine hemostasis. The animals were randomly divided into group A (extra-abdominal compression), group B (gauze packing), group C (intra-abdominal compression), group D (CELOX coverage), and group E (intra-abdominal compression and CELOX coverage) with six swines per group. Survival time (ST), blood loss (BL), vital signs, pathologic examination, and CT-scan were monitored to further observe the effectiveness of the device. 

Results: Group E had an average 30-minute extension in ST (74.3 ± 15.4 minutes versus 44.0 ± 13.8 minutes, p = 0.026) with less BL (46.0 ± 13.0 versus 70.8 ± 8.2 g/kg, p = 0.018), and maintained mean arterial pressure≥70 mmHg and cardiac output ≥ 3.5 L/minute for a longer time. No significant differences were observed in ST and BL of groups B and E, and there were no marked differences in ST and BL of groups A, C, and D. No CELOX clots were noted in the spleen, pancreas, lungs, heart, kidneys, or the adjacent large vessels in groups D and E. Compared to group A, the CT-scan showed better hepatic hemorrhage control in group E. 

Conclusions: The device, which combined 20 g of CELOX particles and 20 pieces of CELOX (8 g) sponge tablets with 50-mmHg intra-abdominal compression for 10 minutes, prolonged the ST by an average of 30 minutes with less BL. It was not markedly different from the full four quadrants gauze packing of liver in hemostatic effect, with no CELOX clot formation in other organs.

Validation of a point-of-care capillary lactate measuring device (Lactate Pro 2)

Anette Raa, Geir Arne Sunde, Bjørn Bolann , Reidar Kvåle, Christopher Bjerkvig, Håkon S Eliassen, Tore Wentzel-Larsen, Jon-Kenneth Heltne 

Scand J Trauma Resusc Emerg Med. 2020 Aug 18;28(1):83 

Background: The measurement of lactate in emergency medical services has the potential for earlier detection of shock and can be performed with a point-of-care handheld device. Validation of a point-of-care handheld device is required for prehospital implementation. 

Aim: The primary aim was to validate the accuracy of Lactate Pro 2 in healthy volunteers and in haemodynamically compromised intensive care patients. The secondary aim was to evaluate which sample site, fingertip or earlobe, is most accurate compared to arterial lactate. 

Methods: Arterial, venous and capillary blood samples from fingertips and earlobes were collected from intensive care patients and healthy volunteers. Arterial and venous blood lactate samples were analysed on a stationary hospital blood gas analyser (ABL800 Flex) as the reference device and compared to the Lactate Pro 2. We used the Bland-Altman method to calculate the limits of agreement and used mixed effect models to compare instruments and sample sites. A total of 49 intensive care patients with elevated lactate and 11 healthy volunteers with elevated lactate were included. 

Results: There was no significant difference in measured lactate between Lactate Pro 2 and the reference method using arterial blood in either the healthy volunteers or the intensive care patients. Capillary lactate measurement in the fingertip and earlobe of intensive care patients was 47% (95% CI (29 to 68%), p < 0.001) and 27% (95% CI (11 to 45%), p < 0.001) higher, respectively, than the corresponding arterial blood lactate. In the healthy volunteers, we found that capillary blood lactate in the fingertip was 14% higher than arterial blood lactate (95% CI (4 to 24%), p = 0.003) and no significant difference between capillary blood lactate in the earlobe and arterial blood lactate. 

Conclusion: Our results showed that the handheld Lactate Pro 2 had good agreement with the reference method using arterial blood in both intensive care patients and healthy volunteers. However, we found that the agreement was poorer using venous blood in both groups. Furthermore, the earlobe may be a better sample site than the fingertip in intensive care patients.

The role of ultrasound in front-of-neck access for cricothyroid membrane identification: A systematic review

Yeshith Rai, Eric You-Ten, Fabricio Zasso, Charmaine De Castro, Xiang Y Ye, Naveed Siddiqui 

J Crit Care. 2020 Dec;60:161-168 

Purpose: Conventional palpation techniques for cricothyroid membrane (CTM) identification are inaccurate and unreliable. Ultrasound plays a multi-faceted role in airway management, however there is limited literature around its use for CTM identification prior to cricothyrotomies. This review sought to compare ultrasound to palpation in the general population, identify its indications in subjects with ill-defined neck anatomy, and determine its role in defining neck anatomy. 

Methods: Two reviewers independently assessed titles, abstracts and full-text English articles through the Ovid Medline and EMBASE databases. Studies related to ultrasound for CTM assessment and/or cricothyrotomy in subjects older than 12 years were included. 

Results: Fourteen studies were selected. Compared to palpation, ultrasound has greater accuracy, but longer CTM identification times in those with normal airway anatomy. Interestingly, ultrasound offers comparable times to palpation in patients with difficult airways. Ultrasound also helps define anatomical parameters in the neutral and extended neck positions thereby underscoring the importance of neck positioning during cricothyrotomies and confirming consensus-based incision recommendations set by the Difficult Airway Society. 

Conclusion: Ultrasound appears to be superior to palpation for CTM localization especially in those with difficult airway anatomy and objectively defines neck anatomy. Its pre-emptive use should be incorporated during difficult airway management.

Developing clinical performance indicators for pre-hospital blood transfusion: The Thames Valley Air Ambulance approach.

James Raitt, Nicola Curry, Pip Lewis, James Dearman, Kurtis Poole, Dhushy Surendra Kuma

Transfus Med 2020 Apr;30(2):134-140 

Objective: In this article, we describe how we developed and validated key performance indicators (KPIs) for pre-hospital blood transfusion and offer suggestions for other organisations wishing to develop performance metrics.

Background: KPIs are metrics that compare actual care against an ideal structure, process or outcome standard. An increasing number of UK-based pre-hospital critical care services now carry blood components to enable pre-hospital blood transfusion.

Methods: A working group of pre-hospital physicians and paramedics was formed to create and validate performance indicators that reflected a high-quality pre-hospital transfusion. This was performed by literature searching and reviewing consensus documents that guide the best practice and then adjusting the indicators as the process evolved.

Results: Throughout the year, the performance against the domains was monitored monthly and outputs communicated within the clinical staff of the organisation; at the end of the year, the domains were amended. The final list of performance indicators was as follows: (a) rationale for transfusion documented in the notes; (b) rationale for transfusion in line with Thames Valley Air Ambulance blood transfusion guideline; (c) aggressive management of hypothermia; (d) tranexamic acid administered within an hour of injury; (e) evidence of bleeding in hospital; (f) monitoring of adverse effects of blood transfusion; (g) overall-was the use of blood justified; and (h) no units wasted this month.

Conclusions: This study has shown that it is feasible to devise and implement clinical performance indicators for pre-hospital blood transfusion and that their use has increased the focus on this important area.

A New Understanding of the Mechanism of Injury to the Pelvis and Lower Limbs in Blast

Iain A Rankin, Thuy-Tien Nguyen, Diagarajen Carpanen, Jonathan C Clasper, Spyros D Masouros 

Front Bioeng Biotechnol. 2020 Aug 13;8:960 

Abstract 

Dismounted complex blast injury (DCBI) has been one of the most severe forms of trauma sustained in recent conflicts. This injury has been partially attributed to limb flail; however, the full causative mechanism has not yet been fully determined. Soil ejecta has been hypothesized as a significant contributor to the injury but remains untested. In this study, a small-animal model of gas-gun mediated high velocity sand blast was used to investigate this mechanism. The results demonstrated a correlation between increasing sand blast velocity and injury patterns of worsening severity across the trauma range. This study is the first to replicate high velocity sand blast and the first model to reproduce the pattern of injury seen in DCBI. These findings are consistent with clinical and battlefield data. They represent a significant change in the understanding of blast injury, producing a new mechanistic theory of traumatic amputation. This mechanism of traumatic amputation is shown to be high velocity sand blast causing the initial tissue disruption, with the following blast wind and resultant limb flail completing the amputation. These findings implicate high velocity sand blast, in addition to limb flail, as a critical mechanism of injury in the dismounted blast casualty.

Evolution of the United States Military Extracorporeal Membrane Oxygenation Transport Team

Matthew D Read, Jason J Nam, Mauer Biscotti, Lydia C Piper, Sarah B Thomas, Valerie G Sams, Bernadette S Elliott, Kathryn A Negaard, James H Lantry, Jeffry D DellaVolpe, Andriy Batchinsky, Jeremy W Cannon, Phillip E Mason 

Mil Med. 2020 Dec 30;185(11-12):e2055-e2060 

Introduction: The use of extracorporeal membrane oxygenation (ECMO) for the care of critically ill adult patients has increased over the past decade. It has been utilized in more austere locations, to include combat wounded. The U.S. military established the Acute Lung Rescue Team in 2005 to transport and care for patients unable to be managed by standard medical evacuation resources. In 2012, the U.S. military expanded upon this capacity, establishing an ECMO program at Brooke Army Medical Center. To maintain currency, the program treats both military and civilian patients. 

Materials and methods: We conducted a single-center retrospective review of all patients transported by the sole U.S. military ECMO program from September 2012 to December 2019. We analyzed basic demographic data, ECMO indication, transport distance range, survival to decannulation and discharge, and programmatic growth. 

Results: The U.S. military ECMO team conducted 110 ECMO transports. Of these, 88 patients (80%) were transported to our facility and 81 (73.6%) were cannulated for ECMO by our team prior to transport. The primary indication for ECMO was respiratory failure (76%). The range of transport distance was 6.5 to 8,451 miles (median air transport distance = 1,328 miles, median ground transport distance = 16 miles). In patients who were cannulated remotely, survival to decannulation was 76% and survival to discharge was 73.3%. 

Conclusions: Utilization of the U.S. military ECMO team has increased exponentially since January 2017. With an increased tempo of transport operations and distance of critical care transport, survival to decannulation and discharge rates exceed national benchmarks as described in ELSO published data. The ability to cannulate patients in remote locations and provide critical care transport to a military medical treatment facility has allowed the U.S. military to maintain readiness of a critical medical asset.

Interventions Performed on Multipurpose Military Working Dogs in the Prehospital Combat Setting: A Comprehensive Case Series Report

Lauren K Reeves, Alejandra G Mora, Amy Field, Theodore T Redman 

J Spec Oper Med. Fall 2019;19(3):90-93 

Introduction: The military working dog (MWD) has been essential in military operations such as Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF). MWDs sustain traumatic injuries that require point of injury and en route clinical interventions. The objective of this study was to describe the injuries and treatment military working dogs received on the battlefield and report their final disposition. 

Methods: This was a convenience sample of 11 injury and treatment reports of US MWDs from February 2008 to December 2014. We obtained clinical data regarding battlefield treatment from the 160th Special Operations Aviation Regiment (SOAR) database and supplemental operational sources. A single individual collected the data and maintained the dataset. The data collected included mechanism of injury, clinical interventions, and outcomes. We reported findings as frequencies. 

Results: Of the 11 MWD casualties identified in this dataset, 10 reports had documented injuries secondary to trauma. Eighty percent of the cases sustained gunshot wounds. The hindlegs were the most common site of injury (50%); however, 80% sustained injuries at more than one anatomical location. Seventy percent of cases received at least one clinical intervention before arrival at their first treatment facility. The most common interventions included trauma dressing (30%), gauze (30%), chest seal (30%), and pain medication (30%). The survival rate was 50%. 

Conclusion: The majority of the MWD cases in this dataset sustained traumatic injuries, with gunshot being the most common mechanism of injury. Most MWDs received at least one clinical intervention. Fifty percent did not survive their traumatic injuries.

Lung Injury Is a Predictor of Cerebral Hypoxia and Mortality in Traumatic Brain Injury

Chiara Robba, Shadnaz Asgari, Amit Gupta, Rafael Badenes, Mypinder Sekhon, Erta Bequiri, Peter J Hutchinson, Paolo Pelosi, Arun Gupta 

Front Neurol. 2020 Aug 7;11:771 

Background: A major contributor to unfavorable outcome after traumatic brain injury (TBI) is secondary brain injury. Low brain tissue oxygen tension (PbtO2) has shown to be an independent predictor of unfavorable outcome. Although PbtO2 provides clinicians with an understanding of the ischemic and non-ischemic derangements of brain physiology, its value does not take into consideration systemic oxygenation that can influence patients' outcomes. This study analyses brain and systemic oxygenation and a number of related indices in TBI patients: PbtO2, partial arterial oxygenation pressure (PaO2), PbtO2/PaO2, ratio of PbtO2 to fraction of inspired oxygen (FiO2), and PaO2/FiO2. The primary aim of this study was to identify independent risk factors for cerebral hypoxia. Secondary goal was to determine whether any of these indices are predictors of mortality outcome in TBI patients.  

Methods: A single-centre retrospective cohort study of 70 TBI patients admitted to the Neurocritical Care Unit (NCCU) at Cambridge University Hospital in 2014-2018 and undergoing advanced neuromonitoring including invasive PbtO2 was conducted. Three hundred and three simultaneous measurements of PbtO2, PaO2, PbtO2/PaO2, PbtO2/FiO2, PaO2/FiO2 were collected and mortality at discharge from NCCU was considered as outcome. Generalized estimating equations were used to analyse the longitudinal data. 

Results: Our results showed PbtO2 of 28 mmHg as threshold to define cerebral hypoxia. PaO2/FiO2 found to be a strong and independent risk factor for cerebral hypoxia when adjusting for confounding factor of intracranial pressure (ICP) with adjusted odds ratio of 1.78, 95% confidence interval of (1.10-2.87) and p-value = 0.019. With respect to TBI outcome, compromised values of PbtO2, PbtO2/PaO2, PbtO2/FiO2, and PaO2/FiO2 were all independent predictors of mortality while considered individually and adjusting for confounding factors of ICP, age, gender, and cerebral perfusion pressure (CPP). However, when considering all the compromised values together, only PaO2/FiO2 became an independent predictor of mortality with adjusted odds ratio of 3.47 (1.20-10.04) and p-value = 0.022. 

Conclusions: Brain and Lung interaction in TBI patients is a complex interrelationship. PaO2/FiO2 seems to be a major determinant of cerebral hypoxia and mortality. These results confirm the importance of employing ventilator strategies to prevent cerebral hypoxia and improve the outcome in TBI patients.

Lung Injury Is a Predictor of Cerebral Hypoxia and Mortality in Traumatic Brain Injury

Chiara Robba, Shadnaz Asgari, Amit Gupta, Rafael Badenes, Mypinder Sekhon, Erta Bequiri, Peter J Hutchinson, Paolo Pelosi, Arun Gupta 

Front Neurol. 2020 Aug 7;11:771 

Background: A major contributor to unfavorable outcome after traumatic brain injury (TBI) is secondary brain injury. Low brain tissue oxygen tension (PbtO2) has shown to be an independent predictor of unfavorable outcome. Although PbtO2 provides clinicians with an understanding of the ischemic and non-ischemic derangements of brain physiology, its value does not take into consideration systemic oxygenation that can influence patients' outcomes. This study analyses brain and systemic oxygenation and a number of related indices in TBI patients: PbtO2, partial arterial oxygenation pressure (PaO2), PbtO2/PaO2, ratio of PbtO2 to fraction of inspired oxygen (FiO2), and PaO2/FiO2. The primary aim of this study was to identify independent risk factors for cerebral hypoxia. Secondary goal was to determine whether any of these indices are predictors of mortality outcome in TBI patients.

 

Methods: A single-centre retrospective cohort study of 70 TBI patients admitted to the Neurocritical Care Unit (NCCU) at Cambridge University Hospital in 2014-2018 and undergoing advanced neuromonitoring including invasive PbtO2 was conducted. Three hundred and three simultaneous measurements of PbtO2, PaO2, PbtO2/PaO2, PbtO2/FiO2, PaO2/FiO2 were collected and mortality at discharge from NCCU was considered as outcome. Generalized estimating equations were used to analyse the longitudinal data. 

Results: Our results showed PbtO2 of 28 mmHg as threshold to define cerebral hypoxia. PaO2/FiO2 found to be a strong and independent risk factor for cerebral hypoxia when adjusting for confounding factor of intracranial pressure (ICP) with adjusted odds ratio of 1.78, 95% confidence interval of (1.10-2.87) and p-value = 0.019. With respect to TBI outcome, compromised values of PbtO2, PbtO2/PaO2, PbtO2/FiO2, and PaO2/FiO2 were all independent predictors of mortality while considered individually and adjusting for confounding factors of ICP, age, gender, and cerebral perfusion pressure (CPP). However, when considering all the compromised values together, only PaO2/FiO2 became an independent predictor of mortality with adjusted odds ratio of 3.47 (1.20-10.04) and p-value = 0.022. 

Conclusions: Brain and Lung interaction in TBI patients is a complex interrelationship. PaO2/FiO2 seems to be a major determinant of cerebral hypoxia and mortality. These results confirm the importance of employing ventilator strategies to prevent cerebral hypoxia and improve the outcome in TBI patients.

Bleeding control in combat fields with extreme transfer time

Amila Sanjiva Ratnayake, T J Worlton

BMJ Mil Health. 2020 Jun;166(3):203 

No abstract available

Prehospital Life-Saving Interventions Performed on Pediatric Patients in a Combat Zone: A Multicenter Prospective Study

Lauren K Reeves, Shelia C Savell, Joseph K Maddry, Kathleen M Samsey, Alejandra G Mora, Julio R Lairet

Pediatr Crit Care Med 2020 Jul;21(7):e407-e413 

Objectives: We aimed to describe and evaluate prehospital life-saving interventions performed in a pediatric population in the Afghanistan theater of operations.

Design: Our study was a post hoc, subanalysis of a larger multicenter, prospective, observational study.

Setting: We evaluated casualties enrolled upon admission to one of the nine military medical facilities in Afghanistan between January 2009 and March 2014.

Patients: Adult and pediatric (<17 yr old) patients.

Measurements: We conducted initial descriptive analyses followed by comparative tests. For comparative analysis, we stratified the study population (adult vs pediatric), and subsequently, we compared injury descriptions and the interventions performed. Following tests for normality, we used the t test or Wilcoxon rank-sum test (nonparametric) for continuous variables and chi- square or Fisher exact for categorical variables. We reported percentages and 95% CIs.

Main results: We enrolled 2,106 patients, of which 5.6% (n = 118) were pediatric. Eighty-two percent of the pediatric patients were male, and 435 had blast related injuries. A total of 295 prehospital life-saving interventions were performed on 118 pediatric patients, for an average of 2.5 life-saving interventions per patient. Vascular access (IV 96%, intraosseous 91%) and hypothermia prevention-related interventions (69%) were the most common. Incorrectly performed life-saving interventions in pediatric patients were rare (98% of life-saving interventions performed correctly) and n equals to 24 life-saving interventions over the 6-year period were missed. The most common incorrectly performed and missed life-saving interventions were related to vascular access. When compared with adult life-saving interventions received in the prehospital environment, pediatric patients were more likely to receive intraosseous access (p < 0.0001), whereas adult patients were more likely to have a tourniquet placed (p = 0.0019), receive wound packing with a hemostatic agent (p = 0.0091), and receive chest interventions (p = 0.0003).

Conclusions: In our study, the most common intervention was vascular access followed by hypothermia prevention and hemorrhage control. The occurrence of missed or incorrectly performed life-saving interventions were rare.

Meta-Analysis of Failure of Prehospital Endotracheal Intubation in Pediatric Patients

Jhon Jairo Rodríguez, Luis Felipe Higuita-Gutiérrez, Edwar Arturo Carrillo Garcia, Esneider Castaño Betancur, Mauricio Luna Londoño, Sara Restrepo Vargas

Emerg Med Int 2020 May 2;2020:7012508 

Prehospital care is essential for airway preservation in pediatric patients who require early endotracheal intubation to improve oxygenation and prevent aspiration. However, high frequencies of failure of endotracheal intubation have been reported for this age group. We aimed to analyze the frequency of failure of endotracheal intubation in pediatric patients within a prehospital context and compare it with adult patients. Thus, a systematic revision of literature with a meta-analysis was performed using a study search and selection strategy ensuring extensiveness, sensitivity, and reproducibility. Meta-analyses were performed for odds ratio, DerSimonian and Laird's Q test was used to assess heterogeneity, and Egger and Begg's test was used to assess publication bias. Overall, 17 papers and 8772 patients were included, and the main cause of prehospital care was assessed to be trauma. Failed endotracheal intubation frequency was 0.4%-52.6% in pediatric patients. The most frequent complication was with esophageal intubation. Forest plot suggests that risk of failure during intubation of pediatric patients is 3.54 fold higher than that observed for adults. It was concluded that airway management in pediatric patients within a prehospital context is a challenge for prehospital care providers because it entails clear physiological and anatomical differences and a low frequency of exposure to this kind of events as opposed to adults. These differences support a widely higher risk of failure of intubation, suggesting the necessity of consistently trained prehospital care providers to ensure proficiency in technique as well as availability of the required equipment.

Evaluation of Head and Body Kinematics Experienced During Parachute Opening Shock

Mil Med. 2020 Dec 5;usaa519. doi: 10.1093/milmed/usaa519. Online ahead of print. 

Tyler F Rooks, Brian L Novotny, Shannon M McGovern, Andrea Winegar, Bethany L Shivers, Frederick T Brozosk 

Introduction: The U.S. Army conducts airborne operations in order to insert soldiers into combat. Military airborne operations are physically demanding activities with a unique loading environment compared with normal duties. A significant amount of research surrounding airborne operations has focused on assessing the incidence and type of associated injuries as well as the potential risk factors for injuries. During parachute opening shock and other high-acceleration events (e.g., fixed wing flight or vehicle crashes), the neck may be vulnerable to injury if inertial loads overcome the voluntary muscular control of the cervical spine and soft tissue structures. A recent epidemiological survey of sport skydivers showed that the neck, shoulders, and back were the most frequently reported sites of musculoskeletal pain. In addition, the survey indicated that wing loading (a measure of the jumper's weight divided by the size of the parachute canopy) was a potential contributing factor for developing musculoskeletal pain. Recently, there have been efforts to measure the severity of parachute opening shock as an additional potential risk factor for injury; however, no studies have measured both head and body accelerations and no studies have measured head or body angular rate during parachute opening shock. The purpose of this study was to measure and characterize the accelerations and angular rates of both the head and body during parachute opening shock as well as investigate potential factors contributing to higher severity opening shock, which may link to the development of musculoskeletal pain or injury. 

Materials and methods: Data were collected from the U.S. Army Parachute Team, The Golden Knights, under an approved Medical Research and Material Command Institutional Review Board protocol. Subjects were instrumented with a helmet- and body-mounted sensor package, which included three angular rate sensors and three single-axis accelerometers each. Data were collected at 2,500 samples per second. Kruskal-Wallis tests were used to determine if helmet-mounted equipment (e.g., cameras), neck length, neck circumference, or wing loading (the ratio of jump weight to the size of the main parachute canopy) affected the accelerations or angular rates of the head or body. 

Results: A total of 54 jumps conducted by 19 experienced free-fall jumpers were analyzed. For the head, the mean (± SD) resultant accelerations and angular rates were 5.8 (± 1.6) g and 255.9 (± 74.2) degrees per second (deg/s), respectively. For the body, the resultant accelerations and angular rates were 4.3 (± 1.5) g and 181.3 (± 61.2) deg/s, respectively. A wing loading above 1.4 pounds per square foot (lb/ft2) was found to have a significant effect on head (P = .001) and body (P = .001) resultant acceleration as well as body angular rate about the Y-axis (P = .001). 

Conclusions: There is evidence to suggest that wing loading has an influence on individual head and body resultant accelerations. However, no significant effects were found for the other variables (e.g., neck length and circumference, helmet-mounted equipment, etc.). Future research should focus on identifying additional factors that result in changes in accelerations and angular rates of the head and body during parachute opening shock events.

Ambulance management of patients with penetrating truncal trauma and hypotension in Melbourne, Australia

Eva Rosenbaum, Shelley Cox, Karen Smith, Mark Fitzgerald, George Braitberg, Anthony Carpenter, Stephen Bernard

Emerg Med Australas 2020 Apr;32(2):336-343 

Objective: Penetrating truncal trauma with hypotension is uncommon in Australia. Current pre- hospital clinical practice guidelines based on overseas studies recommend expedited transport to definitive trauma care and that i.v. fluid should only be administered to maintain palpable blood pressure.

Methods: A retrospective review included all adult patients with penetrating truncal trauma and hypotension (systolic blood pressure <90 mmHg) attended by emergency medical services in Victoria between January 2006 and December 2018. Patient pre-hospital characteristics and hospital outcomes are described using descriptive statistics. Predictors of fluid resuscitation and mortality were examined using logistic regression analyses.

Results: Between 2006 and 2018 there were 101 hypotensive, penetrating truncal injury major trauma patients in Melbourne, Victoria transported by road ambulance to a major trauma service. The median age of these patients was 38 years (interquartile range [IQR] 27-50) and 85% were male. Median scene time was 16.6 min (IQR 12-26) and median pre-hospital time was 53.0 min (IQR 38-66). Intravenous fluid resuscitation was given in 54.5% of cases. The mechanism of injury was stabbing in 91.1% and gunshot wound in 8.9%. Urgent surgery was required in 72.3% of cases, 32.7% of patients were admitted to the intensive care unit and there were eight deaths (8.3%).

Conclusion: Penetrating truncal trauma with hypotension is rare in Melbourne, Australia with most patients having the injury caused by stabbing rather than shooting. Compared with outcomes reported in the USA and Europe, the mortality rate is low.

Pain in the Prehospital Setting in Rwanda: Results of a Mixed-Methods Quality Improvement Project

A Rosenberg, E Uwitonze, M Dworkin, J P D Guidry, T Cyuzuzo, D Banerjee, K McIntyre, K Carlyle, J M Uwitonze, I Kabagema, T Dushime, S Jayaraman 

Pain Res Manag. 2020 Sep 18;2020:3284623. doi: 10.1155/2020/3284623. eCollection 2020 

Introduction: Pain is a universal human experience tied to an individual's health but difficult to understand. It is especially important in health emergencies. We performed a two-step quality improvement project to assess pain management by the SAMU ambulance service in Kigali, Rwanda, examining how pain is assessed and treated by ambulance staff to facilitate development of standardized guidelines of pain management in the prehospital setting, which did not exist at the time of the study. 

Materials and methods: Deidentified ambulance service records from December 2012 to May 2016 were analyzed descriptively for patient demographics, emergency conditions, pain assessment, and medications given. Then, anonymized, semistructured interviews of ambulance staff were conducted until thematic saturation was achieved. Data were analyzed using a grounded theory approach. 

Results: SAMU managed 11,161 patients over the study period, of which 6,168 (55%) were documented as reporting pain and 5,010 (45%) received pain medications. Men had greater odds of receiving pain medications compared to women (OR = 3.8, 95% CI (3.5, 4.1), p < 0.01). Twenty interviews were conducted with SAMU staff. They indicated that patients communicate pain in different ways. They reported using informal ways to measure pain or a standardized granular numeric scale. The SAMU team reviewed these results and developed plans to modify practices. 

Conclusions: We reviewed the existing quality of pain management in the prehospital setting in Kigali, Rwanda, assessed the SAMU staff's perceptions of pain, and facilitated standardization of prehospital pain management through context-specific guidelines.

Effect of Out-of-Hospital Tranexamic Acid vs Placebo on 6-Month Functional Neurologic Outcomes in Patients With Moderate or Severe Traumatic Brain Injury

Susan E Rowell, Eric N Meier, Barbara McKnight, Delores Kannas, Susanne May, Kellie Sheehan, Eileen M Bulger, Ahamed H Idris, Jim Christenson, Laurie J Morrison, Ralph J Frascone, Patrick L Bosarge, M Riccardo Colella, Jay Johannigman, Bryan A Cotton, Jeannie Callum, Jason McMullan, David J Dries, Brian Tibbs, Neal J Richmond, Myron L Weisfeldt, John M Tallon, John S Garrett, Martin D Zielinski, Tom P Aufderheide, Rajesh R Gandhi, Rob Schlamp, Bryce R H Robinson, Jonathan Jui, Lauren Klein, Sandro Rizoli, Mark Gamber, Michael Fleming, Jun Hwang, Laura E Vincent, Carolyn Williams, Audrey Hendrickson, Robert Simonson, Patricia Klotz, George Sopko, William Witham, Michael Ferrara, Martin A Schreiber 

JAMA. 2020 Sep 8;324(10):961-974 

No Abstract

Warming blood prior to transfusion using latent heat

David Roxby, Magdalena Sobieraj-Teague, Jacoba von Wielligh, Romi Sinha, Bryone Kuss, Anne-Louise Smith, Mark McEwen

Emerg Med Australas 2020 Aug;32(4):604-610 

Abstract

Objective: Major trauma is associated with blood loss and hypothermia. It is common to replace lost fluid with red cells stored at 2-6°C, and/or colloid/crystalloid fluid stored at ambient temperature, thus increasing hypothermia risk. At trauma and medical retrieval sites, mains electricity powered fluid warmers cannot be generally used. Latent heat provides an alternate practical method of portable temperature-controlled intravenous fluid warming. This work investigates the safety and efficacy of a fluid warmer powered by latent heat.

Methods: Twenty-five haematology patients received red cell transfusions, one through a fluid warmer, using latent heat from a super-cooled liquid and one without warming. Temperature of donor red cell units was measured after passing through fluid warmers. Blood samples were collected from red cell units and patients, prior and after each transfusion. These were tested for haemolysis markers (plasma haemoglobin, potassium, lactate dehydrogenase, bilirubin) and for traces of super-cooled liquid. Patient physiological parameters (oxygen saturation, pulse, temperature, blood pressure, respiration) were monitored during each transfusion.

Results: Patient's physiological signs remained stable and no transfusion reactions were observed during warm transfusions. Latent heat fluid warmers increased the temperature of red cell units to approximately 35°C. There were no significant differences in haemolysis markers following warmed and unwarmed transfusions, and no contamination of red cell units by super- cooled liquid was detected.

Conclusion: The latent heat fluid warmer was shown to safely warm transfused blood in a controlled clinical setting.

Life on the battlefield: Valproic acid for combat applications (need link)

Rachel Russo, Michael Kemp, Umar F Bhatti, Manjunath Pai, Glenn Wakam, Ben Biesterveld, Hasan B Alam

J Trauma Acute Care Surg. 2020 Aug;89(2S Suppl 2):S69-S76 

The leading causes of death in military conflicts continue to be hemorrhagic shock (HS) and traumatic brain injury (TBI). Most of the mortality is a result of patients not surviving long enough to obtain surgical care. As a result, there is a significant unmet need for a therapy that stimulates a "prosurvival phenotype" that counteracts the cellular pathophysiology of HS and TBI to prolong survival. Valproic acid (VPA), a well-established antiepileptic therapy for more than 50 years, has shown potential as one such prosurvival therapy. This review details how VPA's role as a nonselective histone deacetylase inhibitor induces cellular changes that promote survival and decrease cellular pathways that lead to cell death. The review comprehensively covers more than two decades worth of studies ranging from preclinical (mice, swine) to recent human clinical trials of the use of VPA in HS and TBI. Furthermore, it details the different mechanisms in which VPA alters gene expression, induces cytoprotective changes, attenuates platelet dysfunction, provides neuroprotection, and enhances survival in HS and TBI. Valproic acid shows real promise as a therapy that can induce the prosurvival phenotype in those injured during military conflict.

Acute Pneumothorax Evaluation and Treatment

Karima R. Sajadi-Ernazarova, Jennifer Martin, Nagendra Gupta 

StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan. 

Pneumothorax - is an accumulation of air or gas in the pleural space (the space between visceral and parietal pleura of the chest cavity), which can impair with ventilation, oxygenation, or both. This condition can vary in its presentation from asymptomatic to life-threatening.

Pneumothorax can subdivide into three broad categories according to the etiology:

  1. Traumatic - resulting from blunt or penetrating chest trauma. Majority of all pneumothoraces are traumatic in origin
  2. Iatrogenic - caused by manipulation by a healthcare provider, such as the insertion of central lines, etc
  3. Spontaneous - a pneumothorax without any apparent cause or inciting event.

Pneumothorax can also be classified based on their physiology into the following types:

  1. Simple - when the air in the pleural space does not communicate with an outside atmosphere, and there is no shift in mediastinum or hemidiaphragm. An example is a pleural laceration from a fractured rib.
  2. Communicating - when there is a defect in a chest wall, such as from a gunshot wound, that causes open communication with an outside atmosphere. This loss of the chest wall integrity can create an air sucking and a paradoxical lung collapse, thus causing significant ventilatory problems.
  3. Tension - progressive accumulation of air in the pleural cavity causing the shift of mediastinum to the opposite side, resulting in compression of vena cava and other great vessels, decreased diastolic filling, and ultimately compromised cardiac output. It occurs when a chest injury causes a one-valve situation when the air gets into the pleural cavity but is unable to escape freely and thus gets trapped.

Ketamine for the treatment of prehospital acute pain: a systematic review of benefit and harm

Mårten Sandberg, Per Kristian Hyldmo, Poul Kongstad, Kristian Dahl Friesgaard, Lasse Raatiniemi, Robert Larsen, Vidar Magnusson, Leif Rognås, Jouni Kurola, Marius Rehn, Gunn Elisabeth Vist 

BMJ Open. 2020 Nov 24;10(11):e038134 

Background: Few publications have addressed prehospital use of ketamine in analgesic doses. We aimed to assess the effect and safety profile of ketamine compared with other analgesic drugs (or no drug) in adult prehospital patients with acute pain. 

Methods: A systematic review of clinical trials assessing prehospital administration of ketamine in analgesic doses compared with other analgesic drugs or no analgesic treatment in adults. We searched PubMed, EMBASE, Cochrane Library and Epistemonikos from inception until 15 February 2020, including relevant articles in English and Nordic languages. We used the Cochrane and Grading of Recommendations Assessment, Development and Evaluation methodologies and exclusively assessed patient-centred outcomes. Two independent authors screened trials for eligibility, extracted data and assessed risk of bias. 

Results: We included eight studies (2760 patients). Ketamine was compared with various opioids given alone, and intranasal ketamine given with nitrous oxide was compared with nitrous oxide given alone. Four randomised controlled trials (RCTs) and one cluster randomised trial included 699 patients. One prospective cohort included 27 patients and two retrospective cohorts included 2034 patients. Five of the eight studies had high risks of bias. Pain score with ketamine is probably lower than after opioids as demonstrated in a cluster-RCT (308 patients) and a retrospective cohort (158 patients) study, Δvisual analogue scale -0.4 (-0.8 to 0.0) and Δnumeric pain rating scale -3.0 (-3.86 to -2.14), respectively. Ketamine probably leads to less nausea and vomiting (risk ratio (RR) 0.24 (0.11 to 0.52)) but more agitation (RR 7.81 (1.85 to 33)) than opioids. 

Conclusions: This systematic literature review finds that ketamine probably reduces pain more than opioids and with less nausea and vomiting but higher risk of agitation. Risk of bias in included studies is high.

Burns management in the military and humanitarian setting

Amritpal Sandhu, J B T Herron, N A Martin 

BMJ Mil Health. 2020 Dec 24;bmjmilitary-2020-001672. doi: 10.1136/bmjmilitary-2020-001672. Online ahead of print. 

Abstract 

Burns are an unpredictable element of the modern battlespace and humanitarian operations. Most military burns are small and may not be a significant challenge for deployed healthcare assets but usually render the individual combat ineffective until healed. However, larger burns represent a more significant challenge because of the demand for fluid resuscitation therapy, early surgical intervention and regular wound management that can rapidly deplete surgical capabilities. Beyond the initial injury, longer-term consequences, such as psychological morbidity and loss of functional independence, are rarely considered as part of an ongoing care plan. Globally, most of the morbidity and mortality associated with burns are seen in less economically developed countries and are frequently associated with conflicts and natural disasters, but with simple interventions and resources, outcomes in these environments can be markedly improved. Prehospital providers should be confident to manage the initial assessment of a burn, including triaging for evacuation and packaging for safe transfer. This article provides an overview for prehospital providers on the management of thermal burns in military and humanitarian settings, with additional considerations for the management of chemical and electrical injuries.

Tranexamic acid and traumatic brain injuries

Katarina Sanford, Sarah Garcia 

JAAPA. 2020 Dec;33(12):53-54 

Abstract 

The CRASH-3 trial examined the use of tranexamic acid (TXA) in patients with intracranial bleeding secondary to traumatic brain injury. The trial demonstrated that TXA, an antifibrinolytic medication, reduces mortality in patients with mild to moderate head injuries. However, because of the trial's multiple limitations, TXA cannot yet be called the gold standard.

Wilderness Medicine (Hypothermia, Dehydration, and Ankle Injury): A Pediatric Simulation Case for Medical Trainees

Elizabeth Sanseau, Anita Thomas, Rosny Daniel, Julie Augenstein, Douglas Diekema 

MedEdPORTAL. 2020 May 15;16:10900. doi: 10.15766/mep_2374-8265.10900 

Introduction: Wilderness recreation is increasingly popular among people of all ages. Pediatric providers should have the skills to counsel on risk reduction and respond to medical emergencies in remote settings. However, few physicians receive training in wilderness medicine, and this simulation-based curriculum aims to address that gap. 

Methods: The scenario features an adolescent male in a remote setting with hypothermia, dehydration, and an ankle injury. The simulation is not resource intensive, utilizing a simulated patient actor and minimal equipment. The case includes a case description, learning objectives, instructor notes, example of ideal scenario flow, and anticipated management mistakes. A didactic PowerPoint highlighting the learning objectives is included. 

Results: The simulation was carried out over 1 year in various settings, including urban parks, the wilderness, and the classroom, with 35 medical trainees. Thirty participants (11 medical students, eight residents, and 11 fellows) completed postsimulation surveys; more than 86% gave the highest score of 5 (strongly agree) when asked if the simulation improved their understanding of managing hypothermia, dehydration, and ankle injury in the wilderness. 

Discussion: This simulation case trains responders to recognize an injured hiker; activate the emergency response system; initiate appropriate treatment for hypothermia, dehydration, and an ankle injury; and stabilize for transport. It reinforces medical conditions unique to the wilderness, improvisation in managing medical issues outside of the usual health care environment, and teamwork/communication skills. This case has been found to be an effective learning tool for medical students, residents, and fellow physicians alike.

Management of upper extremity war injuries in the subacute period: A review of 62 cases

Abdulkadir Sari, Ismail Bulent Ozcelik, Derya Bayirli, Omer Ayik, Murat Mert, Burak Sercan Ercin, Humam Baki, Berkan Mersa 

Injury. 2020 Nov;51(11):2601-2611 

Objective: In this study, we aimed to describe the relationship between the localization of rarely seen upper extremity war injuries and their complications in the subacute period, and define our preferences for surgery and antibiotic use. 

Methods: Patients with an upper extremity war injury who presented to our institution between 2015 and 2018 were retrospectively evaluated. Data regarding demographics, time between injury and presentation, location of injury, type of damage, complications, treatment methods, infection rates and antibiotic use were recorded. Tissue defects, fracture fixation, neurovascular damage, infection development and treatment approaches were analyzed. 

Results: Sixty-two male patients with isolated upper extremity injuries (mean age: 31.66 ± 8.28 years) were included in the study. The average time between trauma and hospitalization was 14 days. The mean hematocrit (Hct) level at presentation was 36.3 ± 6.8%. Patients had been followed up for an average period of 95.6 ± 32.1 days. Twenty-nine patients (46.8%) had nerve injury, eight (12.9%) had arterial injury that required repair, and 23 had infection (37.1%), of which five developed osteomyelitis. Infection was polymicrobial in nine cases and monobacterial in 14. A positive correlation was found between the presence of fracture and nerve injury (p = 0.013). The frequency of nerve injuries due to gunshot wounds was higher in the mid-section and lower part of the arms and in the proximal forearm when compared to other regions (p = 0.011). The infection rates were significantly higher in patients with fractures (p = 0.033). The mean hematocrit (Hct) level at presentation of the patients with infection (32.1 ± 6.3%) was significantly lower than that of those who did not have infection (38.8 ± 5.9%) (p<0.001). 

Conclusion: Upper extremity war injuries require case-specific solutions. Microbiological samples should be taken prior to empirical antibiotic treatment for infection management and rational antibiotic use principles should be applied according to the culture and antibiogram results. The holistic and ambiguous character of nerve injuries often requires early exploration and combined reconstructive interventions. Arterial injuries can be overlooked by physical examination alone and thus routine angiography should be performed. Completion of the bone and soft tissue reconstructions in the same session using a holistic approach minimizes the possible risks.

Airway Management in the Prehospital, Combat Environment: Analysis of After-Action Reviews and Lessons Learned

Steven G Schauer, Jason F Naylor, Denise Beaumont, Michael D April, Kaori Tanaka, Darren Baldwin, Joseph K Maddry, Tyson E Becker, Robert A De Lorenzo 

J Spec Oper Med. Fall 2020;20(3):62-66 

Introduction: Airway compromise is the second leading cause of potentially survivable death on the battlefield. Studies show that airway management is a challenge in prehospital combat care with high error and missed opportunity rates. Lacking is user information on the perceived reasons for the challenges. The US military uses several performance improvement and field feedback systems to solicit feedback regarding deployed experiences. We seek to review feedback and after-action reviews (AARs) from end-users with specific regard to airway challenges noted. 

Methods: We queried the Center for Army Lessons Learned (CALL), the Army Medical Department Lessons Learned (AMEDDLL), and the Joint Lessons Learned Information System (JLLIS).Our queries comprised a series of search terms with a focus on airway management. Three military emergency medicine expert reviewers performed the primary analysis for lessons learned specific to deployment and predeployment training lessons learned. Upon narrowing the scope of entries to those relevant to deployment and predeployment training, a panel of eight experts performed reviews. The varied nature of the sources lent itself to an unstructured qualitative approach with results tabulated into thematic categories. 

Results: Our initial search yielded 611 nonduplicate entries. The primary reviewers then analyzed these entries to determine relevance to the project-this resulted in 70 deployment- based lessons learned and four training-based lessons learned. The panel of eight experts then reviewed the 74 lessons learned. We categorized 37 AARs as equipment challenges/malfunctions, 28 as training/education challenges, and 9 as other. Several lessons learned specifically stated that units failed to prioritize medic training; multiple comments suggested that units should consider sending their medics to civilian training centers. Other comments highlighted equipment shortages and equipment malfunctions specific to certain mission types (e.g., pediatric casualties, extreme weather). 

Conclusions: In this review of military lessons learned systems, most of the feedback referenced equipment malfunctions and gaps in initial and maintenance training.This review of AARs provides guidance for targeted research efforts based the needs of the end-users.

An Analysis of Airway Interventions in the Setting of Smoke Inhalation Injury on the Battlefield

Steven G Schauer, Jason F Naylor, Gregory Dion, Michael D April, Kevin K Chung, Victor A Convertino 

Mil Med. 2020 Nov 9;usaa370. doi: 10.1093/milmed/usaa370. Online ahead of print 

Introduction: The Committee on Tactical Combat Casualty Care and Capabilities Development and Integration Directorate cite airway burn injuries as an indication for prehospital cricothyrotomy. We sought to build on previously published data by describing for the first time the incidence of prehospital airway interventions in combat casualties who received airway management in the setting of inhalational injuries.15,26 We hypothesized that (1) airway interventions in combat casualties who suffered inhalational injury would have a higher mortality rate than those without airway intervention and (2) prehospital cricothyrotomy was used with greater incidence than endotracheal intubation. 

Materials and methods: Using a previously described Department of Defense Trauma Registry dataset from January 2007 to August 2016, unique casualties with documented inhalational injury were identified. 

Results: Our predefined search codes captured 28,222 (72.8% of all encounters in the registry) of those subjects. A total of 347 (1.2%) casualties had a documented inhalational injury, 27 (7.8%) of those with at least 1 prehospital airway intervention inhalational injuries (0.09% of our dataset [n = 28,222]). Within the subset of patients with an inhalation injury, 23 underwent intubation, 2 underwent cricothyrotomy, 3 had placement of an airway adjunct not otherwise specifically listed, and 1 casualty had both a cricothyrotomy and intubation documented. No casualties had a supraglottic, nasopharyngeal, or oropharyngeal airway listed. Contrary to our hypotheses, of those with an airway intervention, 74.0% survived to hospital discharge. In multivariable regression models, when adjusting for confounders, there was no difference in survival to discharge in those with an airway intervention compared to those without. 

Conclusions: Casualties undergoing airway intervention for inhalation injuries had similar survival adjusting for injury severity, supporting its role when indicated. Without case-specific data on airway status and interventions, it is challenging to determine if the low rate of cricothyrotomy in this population was a result of rapid transport to a more advanced provider capable of performing intubation or cricothyrotomy may not be meeting the needs of the medics.

Prehospital Airway Management in Iraq and Afghanistan: A Descriptive Analysis

Steven G Schauer, Jason F Naylor, Joseph K Maddry, Denise M Beaumont, Cord W Cunningham, Megan B Blackburn, Michael D April

South Med J. 2018 Dec;111(12):707-713 

Objectives: Airway failures are the second leading cause of potentially preventable death on the battlefield. Improvements in airway management depend on identifying current challenges. We sought to build on previously reported data on prehospital, combat airway management. 

Methods: We used a series of emergency department procedure codes to identify patients within the Department of Defense Trauma Registry from January 2007 to August 2016. This is a subanalysis of those with a documented prehospital airway intervention. 

Results: Of the 28,222 patients in our dataset, 1379 (4.9%) had a documented prehospital airway intervention. Airway devices consisted of 49 airway adjuncts (17 nasopharyngeal airways, 2 oropharyngeal airways, remainder listed as unspecified), 230 cricothyrotomies, 1117 endotracheal intubations, and 27 supraglottic airways. Patients undergoing airway intervention were mostly members of the US military (42.2%). Compared with those without airway intervention, they were slightly younger (median 24 vs 25 years, P < 0.001), more frequently injured by explosives (57.7% vs 55.2%, P < 0.001) and gunshot wound (28.7% vs 23.3%, P < 0.001), with higher injury severity scores (composite and by body region) except the superficial body region, and less likely to survive to discharge (73.5% vs 96.6%, P < 0.001). Vecuronium (35.4%) and midazolam (27.9%) were the most frequently used paralytic and sedative, respectively. 

Conclusions: Patients undergoing airway intervention were most frequently injured by explosive or gunshot wound. Intubations and cricothyrotomies were the most frequent airway interventions performed. Patients undergoing interventions were more critically injured, with higher mortality rates. Further research is needed to determine methods to reduce mortality in this critically injured population.

Outcomes of Casualties Without Airway Trauma Undergoing Prehospital Airway Interventions: A Department of Defense Trauma Registry Study

Steven G Schauer, Jason F Naylor, Joseph K Maddry, Fred C Kobylarz, Michael D April Mil Med 2020 Mar 2;185(3-4):e352-e357

Introduction: Airway obstruction is the second leading cause of preventable death on the battlefield. Most airway obstruction occurs secondary to traumatic disruptions of the airway anatomical structures. However, casualties may require airway interventions for other indications (e.g., depressed mental status). We describe casualties undergoing airway intervention in the prehospital, combat setting without apparent upper airway trauma.

Materials and methods: We used a series of emergency department procedure codes to identify patients within the Department of Defense Trauma Registry (DODTR) from January 2007 to August 2016. This is a subgroup analysis of those patients with a documented prehospital airway intervention and no apparent airway trauma as defined by abbreviated injury scale of 0 for body regions 1 (head/neck) and 2 (face).

Results: Our predefined search codes captured 28222 DODTR subjects of whom 409 (1.4%) met criteria for study inclusion. Subjects included members of host nation forces (34%) and civilians (30%). Most subjects sustained injuries in Afghanistan (82%). Explosive (57%) and gunshot wounds (36%) were the most frequent mechanisms of injury. Median injury severity scores were 17. The most common anatomical locations of injuries for included subjects included extremities (53%) and thorax (29%). A majority of subjects underwent intubation (89%); comparatively few casualties underwent placement of a nasopharyngeal airway (2%) or supraglottic airway (2%). The proportion of subjects surviving to hospital discharge was 80% and was highest among subjects undergoing intubation (82%).

Conclusions: In this subgroup analysis of casualties without apparent upper airway trauma, survival rates were lower when compared to our previous report. Higher quality data are necessary to better understand the resuscitation needs of this critically ill subset of combat casualties.

Abdominal aortic and junctional tourniquet versus zone III resuscitative endovascular balloon occlusion of the aorta in a swine junctional hemorrhage model

David W Schechtman, David S Kauvar, Rodolfo De Guzman, I Amy Polykratis, M Dale Prince, Bijan S Kheirabadi, Michael A Dubick

J Trauma Acute Care Surg 2020 Feb;88(2):292-297 

Abstract

Background: Junctional hemorrhage is a leading contributor to battlefield mortality. The Abdominal Aortic and Junctional Tourniquet (AAJT) and infrarenal (zone III) resuscitative endovascular balloon occlusion of the aorta (REBOA) are emerging strategies for controlling junctional hemorrhage, with AAJT currently available in select forward deployed settings and increasing interest in applying REBOA in the military prehospital environment. This study compared the hemostatic, hemodynamic, and metabolic effects of these devices used for junctional hemorrhage control.

Methods: Shock was induced in anesthetized, mechanically ventilated swine with a controlled hemorrhage (20 mL/kg) and closed femur fracture followed by uncontrolled hemorrhage from a partial femoral artery transection (40% total hemorrhage volume). Residual femoral hemorrhage was recorded during 60-minute AAJT (n = 10) or zone III REBOA (n = 10) deployment, and the arterial injury was repaired subsequently. Animals were resuscitated with 15 mL/kg autologous whole blood and observed for 6 hours.

Results: One animal in each group died during observation. Both devices achieved hemostasis with mean residual femoral blood loss in the AAJT and REBOA groups of 0.38 ± 0.59 mL/kg and 0.10 ± 0.07 mL/kg (p = 0.16), respectively, during the 60-minute intervention. The AAJT and REBOA augmented proximal blood pressure equally with AAJT allowing higher distal pressure than REBOA during intervention (p < 0.01). Following device deflation, AAJT animals had transiently lower mean arterial blood pressure than REBOA pigs (39 ± 6 vs. 54 ± 11 mm Hg p = 0.01). Both interventions resulted in similar degrees of lactic acidemia which resolved during observation. Similar cardiac and renal effects were observed between AAJT and REBOA.

Conclusion: The AAJT and REBOA produced similar hemostatic, resuscitative, and metabolic effects in this model of severe shock with junctional hemorrhage. Both interventions may have utility in future military medical operations.

Implementation and Evaluation of Tactical Combat Casualty Care for Army Aviators

Stephen M Scott, Margaret J Carman, Michael E Zychowicz, Mark L Shapiro, Nicholas A True

Mil Med. 2020 Aug 14;185(7-8) 

Introduction: The importance of developing military strategies to decrease preventable death by mitigating hemorrhage and reducing time between the point of injury and surgical intervention on the battlefield is highlighted in previous studies. Successful implementation of Tactical Combat Casualty Care (TCCC) throughout elements of the USA and allied militaries begins to address this need. However, TCCC implementation is neither even nor complete in the larger, conventional force. Army Aviators are at risk for preventable death as they do not receive prehospital care training and are challenged to render prehospital care in the austere environment of helicopter operations. Army aviators are at risk for preventable death due to the challenges to render prehospital care in the austere environment of helicopter operations. Helicopters often fly at low altitudes, engage in direct action in support of ground troops, operate at a great distance from medical facilities, typically do not have medical personnel onboard, and can have long wait times for medical evacuation services due to the far forward nature of helicopter operations. 

Materials and methods: This is a quality improvement pre-post-intervention design study evaluating the implementation of a combat casualty care training program for Army aviators using well-established evidence-based guidelines for providing care to casualties on the battlefield. The evaluation consisted of participants' self-perceived confidence in providing care to a casualty and change in knowledge level in combat casualty care in a pre/post-intervention design. Clinical skills of tourniquet application, nasopharyngeal airway placement, and needle chest decompression were assessed on a pass/fail grading standard. 

Results: A total of 18 participants completed the pre- and post-education surveys. A paired t-test showed a statistically significant increase in total composite scores from pre (M = 24.67, SD = 5.06) to post-education self-efficacy (M = 37.94, SD = 2.10), t (17) = -11.29, p < 0.001. A paired t-test revealed a significant increase in exam scores from pre (M = 70.22, SD = 9.43) to post (M = 87.78, SD = 7.19), t (17) = -7.31, p < 0.001. There was no pre-intervention skills assessment, however, all participants (n = 18, 100%) passed the tourniquet application, needle chest compression, and insertion of nasopharyngeal airway. 

Conclusion: TCCC for Army Aviators is easily implemented, demonstrates an increase in knowledge and confidence in providing prehospital care, and provides effective scenario-based training of necessary psychomotor skills needed to reduce preventable death on the battlefield. TCCC for Army Aviators effectively takes the TCCC for All Combatants curriculum and modifies it to address the unique considerations in treating wounded aviators and passengers, both in flight and after crashes. This project demonstrates on a small scale how TCCC can be tailored to specific military jobs in order to successfully meet the intent of the upcoming All Service Member TCCC course mandated in DoD 1322.24. Beyond Army aviation, this program is easily modifiable for aviators throughout the military and civilian sector.

Perceived versus actual cricothyroid membrane landmarking accuracy by emergency medicine residents and staff physicians

Nicholas Schouela, Michael Y Woo, Andy Pan, Warren J Cheung, Jeffery J Perry

CJEM 2020 Jul;22(4):523-527 

Abstract

Objectives: Cricothyrotomy is an intervention performed to salvage "can't intubate, can't ventilate" situations. Studies have shown poor accuracy with landmarking the cricothyroid membrane, particularly in female patients by surgeons and anesthesiologists. This study examines the perceived versus actual success rate of landmarking the cricothyroid membrane by resident and staff emergency physicians using obese and non-obese models.

Methods: Five male and female volunteers were models. Each model was placed supine, and a point-of-care ultrasound expert landmarked the borders of each cricothyroid membrane; 20 residents and 15 staff emergency physicians were given one attempt to landmark five models.

Overall accuracy and accuracy stratified by sex and obesity status were calculated.

Results: Overall landmarking accuracy amongst all participants was 58% (SD 18%). A difference in accuracy was found for obese males (88%) versus obese females (40%) (difference = 48%, 95% CI = 30-65%, p < 0.0001), and non-obese males (77%) versus non-obese females (46%) (difference = 31%, 95% CI = 12-51%, p = 0.004). There was no association between perceived difficulty and success (correlation = 0.07, 95% CI = -0.081- 0.214, p = 0.37). Confidence levels overall were higher amongst staff physicians (3.0) than residents (2.7) (difference = 0.3, 95% CI = 0.1-0.6, p = 0.02), but there was no correlation between confidence in an attempt and its success (p = 0.33).

Conclusion: We found that physicians demonstrate significantly lower accuracy when landmarking cricothyroid membranes of females. Emergency physicians were unable to predict their own accuracy while landmarking, which can potentially lead to increased failed attempts and a longer time to secure the airway. Improved training techniques may reduce failed attempts and improve the time to secure the airway.

How effective are different models of pelvic binders: results of a study using a Pelvic Emergency Simulator

Uwe Schweigkofler, Dennis Wincheringer, Jörg Holstein, Tobias Fritz, Reinhard Hoffmann, Tim Pohlemann, Steven C Herath

Eur J Trauma Emerg Surg 2020 May 26;Online ahead of print 

Background: The application of pelvic binders in the preclinical and early clinical phase is advisable to avoid or treat C-problems in unstable and potential bleeding pelvic ring fractures, even if the clinical effectivity is not completely proved. The use for pathologies in the posterior pelvic ring is still debatable.

Questions/purposes: We determined if there is a difference in achievable compression in the dorsal pelvic ring depending on position and pelvic binder model. Can this effect be tested with a simplified artificial model?

Methods: We simulated a Tile type C fracture within the established pelvic emergency trainer and measured in a test series the effectivity of reduction with a non-invasive stabilization technique using 3 different pelvic binders.

Results: Any therapeutic effect of a pelvic binder with compression to the posterior pelvic ring requires at first a reduction maneuver. While the compression effect in the symphysis depends only on positioning of the binder, in the posterior pelvic ring, the result varies with the used model. The achievable pressure in the SI joint with a pelvic binder is only 20-25% (33.5-47 N) compared to the C-Clamp values (156 N).

Conclusions: The use of pelvic binders for non-invasive pelvic ring stabilization, even with a posterior pathology, could be proven in a simplified fracture model. A proper fracture reduction and an adequate device positioning influence the effectiveness.

Clinical relevance: The use of an emergency pelvic trainer even for a non-invasive maneuver is advisable.

Prehospital Battlefield Casualty Intervention Decision Cognitive Study

Marc A Schweizer, David Wampler, Kevin Lu, Andrew S Oh, Stephen J Rahm, Nicholas M Studer, Cord W Cunningham

Mil Med 2020 Jan 7;185(Suppl 1):274-278 

Abstract

Introduction: Airway compromise is the third most common cause of preventable battlefield death. Surgical cricothyroidotomy (SC) is recommended by Tactical Combat Casualty Care (TCCC) guidelines when basic airway maneuvers fail. This is a descriptive analysis of the decision-making process of prehospital emergency providers to perform certain airway interventions.

Methods: We conducted a scenario-based survey using two sequential video clips of an explosive injury event. The answers were used to conduct descriptive analyses and multivariable logistic regression models to estimate the association between the choice of intervention and training factors.

Results: There were 254 respondents in the survey, 176 (69%) of them were civilians and 78 (31%) were military personnel. Military providers were more likely to complete TCCC certification (odds ratio [OR]: 13.1; confidence interval [CI]: 6.4-26.6; P-value < 0.001). The SC was the most frequently chosen intervention after each clip (29.92% and 22.10%, respectively). TCCC-certified providers were more likely to choose SC after viewing the two clips (OR: 1.9; CI: 1.2-3.2; P-value: 0.009), even after controlling for relevant factors (OR: 2.3; CI: 1.1-4.8; P-value: 0.033).

Conclusions: Military providers had a greater propensity to be certified in TCCC, which was found to increase their likelihood to choose the SC in early prehospital emergency airway management.

Implementation and Evaluation of Tactical Combat Casualty Care for Army Aviators

Stephen M Scott, Margaret J Carman, Michael E Zychowicz, Mark L Shapiro, Nicholas A True

Mil Med 2020 Aug 14;185(7-8):e1271-e1276 

Introduction: The importance of developing military strategies to decrease preventable death by mitigating hemorrhage and reducing time between the point of injury and surgical intervention on the battlefield is highlighted in previous studies. Successful implementation of Tactical Combat Casualty Care (TCCC) throughout elements of the USA and allied militaries begins to address this need. However, TCCC implementation is neither even nor complete in the larger, conventional force. Army Aviators are at risk for preventable death as they do not receive prehospital care training and are challenged to render prehospital care in the austere environment of helicopter operations. Army aviators are at risk for preventable death due to the challenges to render prehospital care in the austere environment of helicopter operations.

Helicopters often fly at low altitudes, engage in direct action in support of ground troops, operate at a great distance from medical facilities, typically do not have medical personnel onboard, and can have long wait times for medical evacuation services due to the far forward nature of helicopter operations.

Materials and methods: This is a quality improvement pre-post-intervention design study evaluating the implementation of a combat casualty care training program for Army aviators using well-established evidence-based guidelines for providing care to casualties on the battlefield. The evaluation consisted of participants' self-perceived confidence in providing care to a casualty and change in knowledge level in combat casualty care in a pre/post-intervention design. Clinical skills of tourniquet application, nasopharyngeal airway placement, and needle chest decompression were assessed on a pass/fail grading standard.

Results: A total of 18 participants completed the pre- and post-education surveys. A paired t- test showed a statistically significant increase in total composite scores from pre (M = 24.67, SD= 5.06) to post-education self-efficacy (M = 37.94, SD = 2.10), t (17) = -11.29, p < 0.001. A paired t-test revealed a significant increase in exam scores from pre (M = 70.22, SD = 9.43) to post (M = 87.78, SD = 7.19), t (17) = -7.31, p < 0.001. There was no pre-intervention skills assessment, however, all participants (n = 18, 100%) passed the tourniquet application, needle chest compression, and insertion of nasopharyngeal airway.

Conclusion: TCCC for Army Aviators is easily implemented, demonstrates an increase in knowledge and confidence in providing prehospital care, and provides effective scenario-based training of necessary psychomotor skills needed to reduce preventable death on the battlefield. TCCC for Army Aviators effectively takes the TCCC for All Combatants curriculum and modifies it to address the unique considerations in treating wounded aviators and passengers, both in flight and after crashes. This project demonstrates on a small scale how TCCC can be tailored to specific military jobs in order to successfully meet the intent of the upcoming All Service Member TCCC course mandated in DoD 1322.24. Beyond Army aviation, this program is easily modifiable for aviators throughout the military and civilian sector.

Cut to Air

Mary Scott-Herring, Ionela Morosanu, Jason Bates, Bonjo Batoon AANA J 2020 Apr;88(2):116-120. 

A "cannot ventilate, cannot intubate" scenario is a rare, high-risk anesthesia event. Cricothyrotomy is the final step, but anesthesia training and maintenance of surgical airway skills is variable. The ability to "cut to air" when one performs a cricothyrotomy may be all that prevents a patient from experiencing anoxic brain injury or death. Forty-three Certified Registered Nurse Anesthetists (CRNAs) performed emergency cricothyrotomies on a simulation manikin. Three techniques were available: (1) cricothyrotomy kit, (2) scalpel and tracheostomy, and (3) scalpel/bougie/endotracheal tube. Technique selection and performance were recorded until successful confirmation of placement was achieved in less than 2 minutes. Confidence levels performing cricothyrotomy were also measured before and after simulation. Most CRNAs (53.5%) selected the cricothyrotomy kit, and all but 1 completed the cricothyrotomy in under 2 minutes. The scalpel/bougie/endotracheal tube combination was the fastest, with an average completion time of 86.6 seconds. The confidence of CRNAs in performing a successful cricothyrotomy in less than 2 minutes was significantly increased (P ≤ .001). Simulating airway skills improved performance, speed, and confidence. Because not all CRNAs have had extensive education in performing surgical airways and practicing these skills, simulation may have additional value in developing and maintaining skills and confidence.

 

Efficacy of continuous positive airway pressure in casualties suffering from primary blast lung injury: A modeling study

Timothy E Scott, Mainul Haque, Anup Das, Ian Cliff, Declan G Bates, Jonathan G Hardman

Conf Proc IEEE Eng Med Biol Soc 2019 Jul;2019:4965-4968 

Abstract

Primary blast lung injury is the most important component of a multisystem syndrome of injury that results from exposure to an explosive shockwave. The majority of such casualties require ventilation in an intensive care unit. We describe the use of a novel primary blast lung injury simulator to evaluate the potential efficacy of continuous positive airway pressure in 6 in silico casualties over 24 hours after injury. Our results suggest that primary blast lung injury is a form of acute lung injury that can be effectively managed with continuous positive airway pressure. In austere environments or in circumstances where medical resources are overwhelmed, continuous positive airway pressure using ambient air may be of benefit.

Ability of Layperson Callers to Apply a Tourniquet Following Protocol-Based Instructions From an Emergency Medical Dispatcher

Greg Scott, Christopher Olola, Marie Isabel Gardett, Daniel Ashwood, Meghan Broadbent, Srilakshmi Sangaraju, Paul Stiegler, Mark Conrad Fivaz, Jeff J Clawson

Prehosp Emerg Care 2020 Mar 3;1-8 Online ahead of print. 

Abstract

Introduction: One of the greatest casualty-care improvements resulting from US military operations in Iraq and Afghanistan has been the reduction of preventable death from massive extremity hemorrhage - largely due to the widespread use of limb tourniquets. More recently, tourniquet use in civilian, prehospital settings has shown promise in reducing deaths in cases of catastrophic arterial limb hemorrhage. Telephone instructions by trained emergency medical dispatchers (EMDs) on applying an available tourniquet may help achieve such a benefit.

Objectives: The objective of the study was to determine whether layperson callers can effectively stop simulated bleeding using an improvised or a commercial tourniquet, when provided with scripted instructions via phone from a trained protocol-aided EMD.

Methods: This was a prospective, randomized trial involving layperson volunteers, done at four locations in Salt Lake City, Utah, USA. Volunteers were assigned randomly to three groups: one for each of two commonly available commercial tourniquets and one for an improvised tourniquet.

Results: A total of 246 subjects participated in the study at the four locations between February 11, 2019 and June 22, 2019. The overall median time for all trials (i.e., elapsed time from the start to the end of the simulation) was 3 minutes and 19 seconds. Median time to stop the bleeding (i.e., elapsed time from the start of the simulation to the time the participant was able to successfully stop the bleeding) was 2 minutes and 57 seconds. Median tourniquet pressure was 256 mmHg and median-end blood loss was 1,365 mL. A total of 198 participants (80.49%) were able to completely stop the bleeding while 16 participants (6.5%) had the tourniquet applied with some bleeding still occurring, and 32 participants (13.01%) exceeded the threshold of 2,500 mL of blood loss, resulting in the "patient" not surviving.

Conclusions: The study findings demonstrated that untrained bystanders provided with instructions via phone from a trained Emergency Medical Dispatcher applied a tourniquet and successfully stopped the bleeding completely in most cases.

Cognitive skills of emergency medical services crew members: a literature review

Martin Sedlár

BMC Emerg Med 2020 May 29;20(1):44 

Background: Situation awareness and decision making, listed in non-technical skills taxonomies, are critical for effective and safe performance in high-risk professions. These cognitive skills and their behavioral markers have been studied less in emergency medical services (EMS) crew members. This paper aims to review the existing literature and identify important aspects and behavioral markers of situation awareness and decision making in EMS crew members - those who work in the role of prehospital emergency care providers - and to synthesize findings as a basis for developing a rating and training tool.

Method: The search for relevant articles was conducted using electronic databases, reference lists of relevant reviews and included articles and personal collection of articles. The selection process based on the PRISMA statement yielded a total of 30 articles that met the eligibility criteria. Their findings were qualitatively synthesized using the structured approach, informed by the already known structure: situation awareness and its elements (gathering information, interpreting information, anticipating future states), decision making and its elements (generating and considering options, selecting and implementing an option, reviewing outcome/decision). Moreover, the element of maintaining standards also emerged as highly relevant for cognitive skills.

Results: This review found an increased research interest in the non-technical cognitive skills of EMS crew members. The majority of included articles' research designs were qualitative, then mixed, Delphi, and quantitative. It revealed several specifics of cognitive skills, such as EMS crew members need to holistically assess a wide range of cues and information, to make various health- and safety-related decisions and take EMS standards into account. However, there was only a limited number of observable markers of cognitive skills, such as acts and verbalizations, that could be considered as examples of good behavior. In addition, findings indicate a lack of articles focused on mass-casualty incidents and the interconnection of cognitive skills with other non-technical and medical skills.

Conclusion: Further research is needed to get a more comprehensive view of behavioral markers of cognitive skills and to develop a rating and training tool to improve EMS crew members' cognitive performance.

Transfusion of blood components containing ABO-incompatible plasma does not lead to higher mortality in civilian trauma patients

Jansen N Seheult, Nancy M Dunbar, John R Hess, Erin E Tuott, Mohammad Bahmanyar, Jessica Campbell, Magali Fontaine, Jenna Khan, Ara Ko, Jian Mi, Michael F Murphy, Tara Nykoluk, Jessica Poisson, Jay S Raval, Andrew Shih, Jason L Sperry, Julie Staves, Michelle Wong, Matthew T S Yan, Alyssa Ziman, Mark H Yazer, Biomedical Excellence for Safer Transfusion (BEST) collaborative 

Transfusion. 2020 Nov;60(11):2517-2528 

Background: This study investigated the effect on mortality of transfusing ABO-incompatible plasma from all sources during trauma resuscitation. 

Methods: Demographic, transfusion, and survival data were retrospectively extracted on civilian trauma patients. Patients were divided by receipt of any quantity of ABO-incompatible plasma from any blood product (incompatible group) or receipt of solely ABO-compatible plasma (compatible group). The primary outcome was 30-day mortality, while other outcomes included 6- and 24-hour mortality. Mixed-effects logistic regression was used to model the effect of various predictor variables, including receipt of incompatible plasma, on mortality outcomes. 

Results: Nine hospitals contributed data on a total of 2618 trauma patients. There were 1282 patients in the incompatible group and 1336 patients in the compatible group. In both the unadjusted and adjusted models, the 6-hour, 24-hour, and 30-day mortality rates were not significantly different between these groups. The patients in the incompatible group were then divided into high volume (>342 mL) and low volume (≤342 mL) incompatible plasma recipients. In the adjusted model, the high-volume group had higher 24-hour mortality when the Trauma Injury Severity Score survival prediction was >50%. Mortality at 6 hours and 30 days was not higher in this model. The low-volume group did not have increased mortality at any of the time points in this adjusted model. 

Conclusion: The transfusion of incompatible plasma in civilian trauma resuscitation does not lead to higher 30-day mortality. The finding of higher mortality in a select group of recipients in the secondary analysis warrants further study.

Developing Cricothyroidotomy Skills Using a Biomaterial-Covered Model

Cigdem Ozkaya Senuren, Serpil Yaylaci, Kamil Kayayurt, Hasan Aldinc, Cem Gun, Perihan Şimşek, Ozgur Tatli, Suha Turkmen 

Wilderness Environ Med. 2020 Sep;31(3):291-297 

Introduction: Cricothyroidotomy is an advanced and life-saving technique, but it is also a rare and a difficult procedure. The purpose of the present study was to produce a low-cost simulation model with realistic anatomic features to investigate its effectiveness in developing cricothyroidotomy skills. 

Methods: This study was performed at a university simulation center with 57 second-year student paramedics and a cricothyroidotomy simulation model. Total scores were assessed using a checklist. This consisted of 13 steps and was scored as misapplication/omission=0, correct performance and timing with hesitation=1, and correct performance and timing without hesitation=2. One of these steps, local anesthesia of the area if time is available, was not performed owing to time limitations. The highest possible score was 24. Data are presented as mean±SD with range, as appropriate. Normal distribution was evaluated using the Kolmogorov-Smirnov test, Student t test, and Mann-Whitney U test, and correlation analysis was used for statistical analysis. 

Results: Students completed the cricothyroidotomy procedure steps in 116±46 (55-238) s. At performance assessment, the score achieved was 12±5 (2-24). The highest total score of 24 was achieved by 3 students (5%). Total scores exhibited negative and significant correlation with procedure time (r=-0.403, P=0.002). 

Conclusions: The model developed in this study is an inexpensive and effective method that can be used in cricothyroidotomy training for student paramedics. We think that repeating the cricothyroidotomy procedure on the model will increase success levels

Pitfalls in Ventilation Devices

Parisa Sezari, Masoud Nashibi, Farhad Safari, Ali Dabbagh, Kamran Mottaghi

Turk J Anaesthesiol Reanim. 2020 Oct;48(5):417-419

 Abstract

Adequate ventilation is the greatest concern of all the anaesthesiologists. Any disturbance in the ventilation process could result in serious hazards: hypoxemia or barotrauma. Deficient devices are one of many causes of such derangements. Some of the typical complications of airway/ventilation tools are described extensively in textbooks, but many other uncommon events can still occur. We described two interesting cases of device-related ventilation inadequacy, hoping that acquaintance with such jeopardizes would be helpful in emergency situations for other colleagues.

Prehospital Blood Transfusion in New South Wales, Australia: A retrospective cohort study

Sophie Shand, Kate Curtis, Michael Dinh, Brian Burns

Prehosp Emerg Care 2020 May 15;1-11 

Introduction: Catastrophic hemorrhage remains the leading cause of preventable death. Not all New South Wales (NSW) hospitals stock blood products and, as such, blood products carried by NSW Ambulance retrieval teams are often the first available to critically unwell patients.

Objective: To describe the trends, characteristics and predictors of mortality prior to hospital treatment in patients receiving prehospital blood transfusion by NSW Ambulance retrieval teams attending primary missions from 2009-2018.

Methods: Retrospective review of all patients who received blood products with NSW Ambulance retrieval teams between 13/8/2009 and 31/12/2018.

Results: A total of 12,468 primary taskings were reviewed, identifying 1,043 (8.4%) cases of prehospital transfusion. The proportion of missions administering blood transfusions doubled between 2009 and 2018. Road traffic incidents were the predominant etiology. Eighty per cent of patients (n = 842) reached hospital alive following transfusion. Retrieval missions had a median time of 117 minutes (IQR 74-168). An initial blood pressure <100mmHg and reduced GCS were strongly associated with prehospital mortality. The median shock index of patients prior to transfusion was 1.2, which reduced to 1.0 after transfusion.

Conclusion: The use of prehospital blood transfusion for suspected bleeding in NSW Australia has more than doubled since 2010. Patients who received prehospital transfusion arrived at hospital with improved hemodynamic observations.

Is Intranasal Ketamine Safe and Effective as a Prehospital Analgesic?

Brett H Shaw 1, Marshall Ross 1

CJEM 2020 Jan;22(1):31-32 

ABSTRACT

Background: Primary care paramedics in British Columbia, Canada, have limited analgesic options other than nitrous oxide when transporting patients. Ketamine can be an effective analgesic when dosed appropriately. 

Objective: The aim of this study was to compare the improvement in pain scores between intranasal ketamine and placebo when added to baseline inhaled nitrous oxide. 

Design: Single-centre randomized double blind control trial. 

Setting: Out-of-hospital patients being cared for by primary care paramedics dispatched from a single station. 

Subjects: Out-of-hospital patients with acute pain who reported a verbal numeric rating scale pain score ≥ 5, and who wished to receive analgesia. 

Intervention: 0.75 mg/kg intranasal ketamine v. placebo, both in addition to baseline nitrous oxide administration. 

Outcomes: Primary outcome was the proportion of patients experiencing a reduction in verbal numeric rating scale score ≥ 2 at 30 minutes.

Synthesis of chitosan iodoacetamides via carbodiimide coupling reaction: Effect of degree of substitution on the hemostatic properties (Need Link)

Jialong Shen, Ahmed Ali Nada, Nabil Yousrie Abou-Zeid, Samuel M Hudson Carbohydr Polym 2020 Feb 1;229:115522

 

Abstract

Uncontrolled hemorrhage continues to be the leading cause of death from traumatic injuries both in the battlefield and in the civilian life. Chitosan is among the very few materials that have made the short list of military recommended field-deployable hemostatic dressings. However, the detailed mechanism of its action is still not fully understood. Moreover, in the cases when patients developed coagulopathy, the efficacy of the dressings rely solely on those mechanisms that work outside of the regular blood coagulation cascade. In addition to the well-known erythrocyte agglutination, we proposed to use the reactive N-iodoacetyl group on a new chitosan derivative to accelerate hemostasis. In this paper, we describe the synthesis of chitosan iodoacetamide (CI) with considerations of the stoichiometry among the reagents, the choice of solvent, the pH of the reaction medium, and the reaction time. The reaction was confirmed by FT-IR, 1H and 13C NMR, elemental analysis, iodine content analysis, and SEM- EDS. Water contact angle measurements and Erythrocyte Sedimentation Rate (ESR) method were used to evaluate the hemostatic potential of the newly synthesized CI as a function of their degree of substitution (DS). The range of DS was 5.9% to 27.8% for CI. The mid-range of DS gave the best results for the ESR. CIs exhibit favorable cytocompatibilities up to DS 18.7 compared to the generic unmodified chitosan. In general, the biocompatibility of chitosan iodoacetamide slightly declined with increasing the iodide content up to DS 21.5 owing to its affinity to SH groups of cells.

The Military Medical System and Wartime Injuries to the Spine

Kartik Shenoy, Yong H Kim

Bull Hosp Jt Dis (2013) 2020;78(1):42-45. 

War has historically been a major catalyst for advancement in military medical care and medicine in general. In our current conflicts, advances in battlefield medicine, evacuation techniques, and personal protective equipment have improved survival rates among members of the armed services. With increased survival, there has been increased prevalence of serious but nonfatal injuries, particularly from blunt and penetrating trauma. Blast injuries are the major cause of trauma and have both blunt and penetrating components. With respect to the spine, blasts have led to open, contaminated wounds that are complex and difficult to treat.

Additionally, blasts have led to an increased incidence of lower lumbar burst fractures and lumbosacral dissociation. As these and other injuries are being seen more commonly during war, we must ensure that our military medical system is adapting to ensure we are taking care of our military personnel at the highest level.

Review of simulation model for education of point-of-care ultrasound using easy-to-make tools

Kyu Chul Shin, Young Rock Ha, Seong-Joon Lee, Jung Hwan Ahn

World J Clin Cases. 2020 Oct 6;8(19):4286-4302 

Abstract 

Point-of-care ultrasound (POCUS) is a powerful diagnostic tool and provides treatment guidelines in acute critical settings. However, the limitation of using POCUS is operator dependent. Appropriate and validated training for acquiring and using skills in practice must be conducted before using POCUS in clinical settings in order to keep patients safe. Simulation education models have been introduced as a way to solve and overcome these concerns. However, the commercial simulator with sufficiently secured fidelity is expensive and not always available. This review focused on the inexpensive and easily made simulators for education on POCUS in critical specific situations related to the airway, breathing, circulation, and disability. We introduced the simulators that used non-infectious materials, with easily transportable features, and that had a sonographic appearance reproducibility similar to human tissue. We also introduced the recipe of each simulator in two parts: Materials surrounding disease simulators (surrounding materials) and specific disease simulators themselves (target simulators). This review article covered the following: endotracheal or oesophageal intubation, lung (A-lines, B-lines, lung sliding, and pleural effusions such as hemothorax), central vein access, pericardial fluid (cardiac tamponade), the structure related to the eyes, soft tissue abscess, nerve (regional nerve block), and skull fracture simulators.

Institution-Specific Machine Learning Models for Prehospital Assessment to Predict Hospital Admission: Prediction Model Development Study

Toru Shirakawa, Tomohiro Sonoo, Kentaro Ogura, Ryo Fujimori, Konan Hara, Tadahiro Goto, Hideki Hashimoto, Yuji Takahashi, Hiromu Naraba, Kensuke Nakamura 

JMIR Med Inform. 2020 Oct 27;8(10):e20324 

Background: Although multiple prediction models have been developed to predict hospital admission to emergency departments (EDs) to address overcrowding and patient safety, only a few studies have examined prediction models for prehospital use. Development of institution-specific prediction models is feasible in this age of data science, provided that predictor-related information is readily collectable. 

Objective: We aimed to develop a hospital admission prediction model based on patient information that is commonly available during ambulance transport before hospitalization. 

Methods: Patients transported by ambulance to our ED from April 2018 through March 2019 were enrolled. Candidate predictors were age, sex, chief complaint, vital signs, and patient medical history, all of which were recorded by emergency medical teams during ambulance transport. Patients were divided into two cohorts for derivation (3601/5145, 70.0%) and validation (1544/5145, 30.0%). For statistical models, logistic regression, logistic lasso, random forest, and gradient boosting machine were used. Prediction models were developed in the derivation cohort. Model performance was assessed by area under the receiver operating characteristic curve (AUROC) and association measures in the validation cohort. 

Results: Of 5145 patients transported by ambulance, including deaths in the ED and hospital transfers, 2699 (52.5%) required hospital admission. Prediction performance was higher with the addition of predictive factors, attaining the best performance with an AUROC of 0.818 (95% CI 0.792-0.839) with a machine learning model and predictive factors of age, sex, chief complaint, and vital signs. Sensitivity and specificity of this model were 0.744 (95% CI 0.716-0.773) and 0.745 (95% CI 0.709-0.776), respectively. 

Conclusions: For patients transferred to EDs, we developed a well-performing hospital admission prediction model based on routinely collected prehospital information including chief complaints.

Commentary on "Austere Resuscitative and Surgical Care in Support of Forward Military Operations-Joint Trauma System Position Paper"

Craig D Shriver, Oliver H Beahrs

Mil Med. 2020 Oct 30;usaa363. doi: 10.1093/milmed/usaa363. Online ahead of print. 

No abstract available

Tactical Combat Casualty Care in Operation Freedom's Sentinel

Anant Shukla, Christian Perez, Benjamin Hoemann, Martin Keasal 

J Spec Oper Med. Fall 2020;20(3):67-70 

Abstract 

Over the course of nearly 19 years of conflict, Tactical Combat Casualty Care (TCCC) guidelines and their implementation have evolved to incorporate the latest advances in trauma research, casualty care, and transport, playing a large role in generating the lowest incidence of preventable deaths in the history of modern warfare. During the conflicts in Afghanistan and Iraq, the adoption and implementation of TCCC principles by conventional forces have been extrapolated to have been responsible for saving the lives of more than 1,000 US Servicemembers. As the intensity and nature of the military conflicts in Afghanistan and Iraq change, and a growing potential for a near peer conflict rises, it remains important that the lessons of TCCC continue to be instilled in our formations in garrison, before deployment, and while in theater. This article reviews the use of TCCC principles by an assault helicopter battalion, in combination with a variety of other factors, in the successful management of a mass casualty event during Operation Freedom's Sentinel 2019 in Afghanistan.

Massive transfusion and the response to prehospital plasma: It is all in how you define it

Edward S Sim, Frank X Guyette, Joshua B Brown, Brian J Daley, Richard S Miller, Brian G Harbrecht, Jeffrey A Claridge, Herb A Phelan, Matthew D Neal, Raquel Forsythe, Brian S Zuckerbraun, Jason L Sperry, PAMPer study group

J Trauma Acute Care Surg 2020 Jul;89(1):43-50 

Abstract

Background: A recent analysis derived from the Prehospital Air Medical Plasma trial data set demonstrated no significant independent plasma survival benefit in those who required massive transfusion (≥10 units of red cells in 24 hours). The definition of massive transfusion has evolved over time to minimize bias and predict those at highest risk of death. We sought to characterize the definition of massive transfusion, their associated mortality risks and the survival benefit associated with prehospital plasma.

Methods: A secondary analysis was performed using data from a recent prehospital plasma trial. Patients transferred directly from the scene were characterized. We defined historic massive transfusion using ≥10 units red cells in 24 hours and critical administration threshold (CAT) as ≥3 units per hour in the first hour (CAT1hr) or in any of the first 4 hours (CAT4hr) from arrival. The primary outcome was 30-day mortality. Kaplan-Meier analysis and Cox hazard regression were used to characterize the survival benefit of prehospital plasma.

Results: There were a total of 390 enrolled patients who were transferred from the scene and represent the study cohort. Overall, 126 patients were positive for the CAT1hr metric, 183 patients were positive for the CAT4hr metric and 84 patients were positive for historic massive transfusion metric. The overall study mortality rate for those patients who met each transfusion definition was 13.1%, 17.4% and 10.0%, respectively. The CAT4hr metric had the lowest potential for survival bias. Kaplan-Meier survival analysis demonstrated a prehospital plasma survival benefit in the patients who were CAT4hr positive.

Conclusion: The current analysis demonstrates the superior utility of the CAT4hr definition with optimization of survival bias while conserving mortality risk prediction. This transfusion definition was associated with a prehospital plasma survival benefit and may be the most appropriate definition of massive transfusion for pragmatic studies which focus on hemorrhagic shock.

Level of evidence: Epidemiologic, Level II.

Hemorrhage Control Training: Preparing Adolescents to Act at Home, at School, or in Public

Richard A Sidwell, Sarah K Spilman, Brian Feist, Elizabeth A Fuchsen, Philip S Taber, Carlos A Pelaez 

Pediatr Emerg Care. 2020 Jun 11. doi: 10.1097/PEC.0000000000002164. Online ahead of print. 

Objectives: Uncontrolled bleeding is the leading cause of preventable death after a traumatic event, and early intervention to control bleeding improves opportunities for survival. It is imperative to prepare for local and national disasters by increasing public knowledge on how to control bleeding, and this preparation should extend to both adults and children. The purpose of this study is to describe a training effort to teach basic hemorrhage control techniques to early adolescent children. 

Methods: The trauma and emergency departments at a combined level I adult and level II pediatric trauma center piloted a training initiative with early adolescents (grades 6-8) focused on 2 skills: packing a wound and holding direct pressure, and applying a Combat Application Tourniquet. Students were evaluated on each skill and completed presurveys and postsurveys indicating their likelihood to use the skills. 

Results: Of the 194 adolescents who participated in the trainings, 97% of the students could successfully pack a wound and hold pressure, and 97% of the students could apply a tourniquet. Before the training, 71% of the adolescents indicated that they would take action to assist a bleeding victim; this increased to 96% after the training. 

Conclusions: Results demonstrate that basic hemorrhage control skills can be effectively taught to adolescents as young as 6th grade (ages 11-12 years) in a small setting with age-appropriate content and hands-on opportunities to practice the skills and such training increases students' perceived willingness to take action to assist a bleeding victim.

Preoperative intravenous meloxicam for moderate-to-severe pain in the immediate post-operative period: a Phase IIIb randomized clinical trial in 55 patients undergoing primary open or laparoscopic colorectal surgery with bowel resection and/or anastomosis

Jennifer D Silinsky, Jorge E Marcet, Vamshi Ruthwik Anupindi, Swapna U Karkare, Drishti R Shah, Randall J Mack, Stewart W McCallum, Wei Du, Alex Freyer, Libby K Black 

Pain Manag. 2021 Jan;11(1):9-21 

Aim: Evaluate safety/efficacy of intravenous meloxicam in a colorectal enhanced recovery after surgery protocol. Methods: Adults undergoing primary open or laparoscopic colorectal surgery with bowel resection and/or anastomosis received meloxicam IV 30 mg (n = 27) or placebo (n = 28) once daily beginning 30 min before surgery. 

Results: Adverse events: meloxicam IV, 85%; placebo, 93%. Adverse events commonly associated with opioids: 41 versus 61% - including nausea (33 vs 50%), vomiting (19 vs 18%) and ileus (4 vs 18%). Wound healing satisfaction scores (physician-rated), clinical laboratory findings and vital signs were similar in both groups. No anastomotic leaks were reported. Opioid consumption, postoperative pain intensity, length of stay and times to first bowel sound, first flatus and first bowel movement were significantly lower with meloxicam IV versus placebo. Most subjects (>92%) were satisfied with postoperative pain medication. 

Conclusion: Meloxicam IV was generally well tolerated and associated with decreased opioid consumption, lower resource utilization and functional benefits.

Randomized Controlled Trial to Compare Baska® Mask versus ProSeal Laryngeal Mask\ Airway for General Anesthesia with Intermittent Positive Pressure Ventilation

Balwinderjit Singh, Arwinder Pal Singh, Joginder Pal Attri 

Anesth Essays Res. Jan-Mar 2020;14(1):25-28 

Introduction: A myriad of supraglottic airway devices (SADs) are developed over time to search the device that conforms to the anatomy of the human respiratory tract noninvasively, but these devices are associated with the risk of aspiration. Baska® mask (BM) is the latest addition to the family of SADs to circumvent the incidence of aspiration. 

Aims of study: The aim of the study was to compare the sealing pressure and rapidity of the insertion of BM with ProSeal laryngeal mask (PLM) airway and the incidence of laryngopharyngeal morbidity between two devices. 

Materials and methods: A randomized prospective open-label study was done on sixty adult patients of the age group of 18-60 years after approval from the institutional ethical committee and registration of trial in the Clinical Trials Registry. The patients were randomly divided into two groups: Group I (BM) where BM was inserted after the induction of general anesthesia and Group II (PLM) where PLM was inserted after induction. The airway sealing pressure in BM was calculated. The mean time of insertion of respective SAD and the number of successful attempts were also recorded in both groups. For analysis of continuous variables, independent sample Student's t-test was applied, and for categorical variables, Chi-square test was used. P < 0.05 was considered statistically significant. 

Results: The rate of successful attempts of insertion was comparable in both the groups. The mean insertion time was 14.25 ± 3.82 s in BM group and 22.01 ± 2.64 s in PLM group, which was statistically significant. The airway sealing pressure was 30.25 ± 3.34 cmH2O in BM group and 23.50 ± 4.05 cmH2O in PLM group, which was also statistically significant. 

Conclusion: BM has better ease of insertion with adequate sealing pressure as compared to PLM airway, thus reducing the chances of aspiration and offering its potential application in securing airway in emergency situations.

The supraglottic airway device as first line of management in anticipated difficult mask ventilation in the morbidly obese

Aparna Sinha, Lakshmi Jayaraman, Dinesh Punhani

J Anaesthesiol Clin Pharmacol Oct-Dec 2019;35(4):540-545 

Abstract

Background and aims: Supraglottic airway devices (SGAs) are used to rescue difficult and failed mask ventilation (DMV). We aimed to use the SGA as first-line device, prior to obtaining a definitive airway and to find any predictors of difficulty for the same, in the morbidly obese patients.

Material and methods: Obese surgical patients [body mass index (BMI) >35 kg/m2] were investigated. Difficulties with bag mask ventilation (MV) was graded using the following scale: MV-1, one anesthesiologist unassisted could achieve MV and maintain SpO2>90%; MV-2, one additional anesthesiologist was needed to facilitate MV to achieve SpO2> 90%; MV-3, two additional anesthesiologists were needed for this purpose; and MV-3P, when a supraglottic device was required to ventilate and maintain SpO2 more than 90%. Parameters studied were age, gender, neck circumference (NC), BMI, STOPBANG score, and safe apnea time (SAT).

Results: Logistic regression was performed for predictors of MV-3P; receiver operating characteristic curve was used to locate the best cut-off. Analysis of 834 morbidly obese patients revealed an incidence of MV 1/2/3/3-P as 16%/38%/27%/19%, respectively. DMV was associated with BMI ≥50 kg/m2, NC ≥49.5 cm, and STOPBANG ≥6; P < 0.001. The mean SAT for a population with mean BMI 48 ± 8 kg/m2 was 256 ± 66 s. The SAT showed inverse relation to BMI and NC. As per our results, the NC was the single most important predictor of MV-3P, with sensitivity 0.62 and specificity 0.85 at best cut-off 49.5 cm; P < 0.001.

Conclusion: NC ≥49.5 cm is strongly associated with low SAT and need for SGA to achieve MV. SGA may provide safety for initial management following induction of anesthesia in this patient population.

Martial arts technique for control of severe external bleeding

John P Slevin, Cierra Harrison, Eric Da Silva, Nathan J White 

Emerg Med J 2019 Mar;36(3):154-158

Objectives: Haemorrhage control is a critical component of preventing traumatic death. Other than the battlefield, haemostatic devices, such as tourniquets or bandages, may not beavailable, allowing for significant avoidable blood loss. We hypothesised that compression of vascular pressure points using a position adapted from the martial art of Brazilian Jiu-Jitsu could be adapted to decrease blood flow velocity in major extremity arteries.

Methods: Knee mount compression was applied to the shoulder, groin and abdomen of healthy adult volunteer research subjects from Seattle, Washington, USA, from March through May 2018. Mean arterial blood flow velocity (MAV) was measured using ultrasound in the brachial and femoral arteries before and after compression. A MAV decrease greater than 20% with compression was deemed clinically relevant.

Results: For 11 subjects, median (IQR) MAV combining all anatomical locations tested was 29.2 (34.1, 24.1) cm/s at baseline and decreased to 3.3 (0, 19.1) cm/s during compression (Wilcoxon p<0.001). MAV was significantly decreased during compression for each individual anatomical position tested (Wilcoxon p≤0.004). Per cent (95% CI) MAV reduction was significantly greater than 20% for shoulder compression at 97.5%(94% to 100%) and groin compression at 78%(56% to 100%), but was not statistically greater for abdominal compression at 35%(12% to 57%). Complete vessel occlusion was most common with compression at the shoulder (73%), followed by groin (55%) and abdomen (9%) (χ² LR, p=0.018).

Conclusion: The Brazilian Jiu-Jitsu knee mount position can significantly decrease blood flow in major arteries of the extremities. This technique may be useful for bleeding control after injury.

Systematic approach to delivering prolonged field care in a prehospital care environment

Michael Smith, K Johnston, R Withnall

BMJ Mil Health 2020 Feb 27; Online ahead of print. 

Abstract

Background: This article describes a novel patient care algorithm which provides a Role 1 (R1) medic with a structured approach to delivering prolonged field care (PFC) in a resource-limited environment. PFC is a vital component of the operational patient care pathway providing the continuum of care from completion of a primary survey to the delivery to hospital care. Future operational environments are likely to have more fragile or extended lines of communication, potentially delaying evacuation to hospital care. This delay may lead to increases in patient morbidity and mortality. Effective PFC offers an opportunity to improve patient outcomes and help mitigate against this risk.

Methods: An initial prototype model of a PFC care process was developed using existing hospital-based guidance. A series of medical and trauma vignettes and best available evidence were used to refine the algorithm.

Results: The algorithm has been designed be used in conjunction with patient specific clinical guidance making the approach generalisable for all patient groups. For UK military, clinical guidance is provided by clinical guidelines for operations. The algorithm can be downloaded into a convenient format to be used on mobile devices or printed as an aide memoire.

The Use of Tranexamic Acid (TXA) for the Management of Hemorrhage in Trauma Patients in the Prehospital Environment: Literature Review and Descriptive Analysis of Principal Themes

Rachel Stansfield, Danielle Morris, Emmanuel Jesulola

Shock 2020 Mar;53(3):277-283 

Abstract

Tranexamic acid (TXA) is an antifibrinolytic agent used to prevent traumatic exsanguination. It was first introduced to clinical practice for the management of patients with bleeding disorders, especially adapted to reduce bleeding in hemophiliacs undergoing oral surgical interventions. TXA exerts its action on the coagulation process by competitively inhibiting plasminogen activation, thereby reducing conversion of plasminogen into plasmin. This ultimately prevents fibrinolysis and reduces hemorrhage. Thus, TXA may be well suited for the management of traumatic hemorrhage in the prehospital setting. Despite multiplicity of studies on the use of TXA in clinical practice, there is no consensus regarding the use of TXA for the management of hemorrhage in trauma patients in the prehospital environment. Thus, a review on this topic was warranted. An extensive literature search yielded 14 full journal articles which met the inclusion criteria. These articles were thoroughly analyzed and the following themes were identified: "dose of TXA administration," "route of TXA administration," "optimal window of TXA administration," "safety of TXA use," "clinical effectiveness of TXA application," and the "feasibility of TXA use in the prehospital setting. "Overall, to achieve the best possible outcomes, the literature supports the use of a loading dose of 1 g of TXA, followed by 1 g infusion over 8 h, given by intravenous administration within a 3-h window period of traumatic injury. TXA is very effective and safe to use in the prehospital setting, and its use is clinically and economically feasible.

Association of Interfacility Helicopter versus Ground Ambulance Transport and in-Hospital Mortality among Trauma Patients

Kenneth Stewart, Tabitha Garwe, Babawale Oluborode, Zoona Sarwar, Roxie M Albrecht 

Prehosp Emerg Care. 2020 Oct 5;1-9. doi: 10.1080/10903127.2020.1817215. Online ahead of print. 

Background: Relatively few studies have compared outcomes between helicopter transport (HT) and ground transport (GT) for the inter-facility transfer of trauma patients to tertiary trauma centers (TTC). Mixed results have been reported from these studies ranging from a slight increase in odds of survival for the severely injured to no evident benefit for HT patients. We hypothesized there was no adjusted difference in mortality between patients transported interfacility by HT or GT taking into account distance from TTC. 

Methods: Data from an inclusive statewide trauma registry was used to conduct a retrospective cohort study of adult (18+ years old) trauma patients who initially presented to a non-tertiary trauma center (NTC) before subsequent transfer by HT or GT to a TTC. Records from the NTC and TTC were linked (N = 9880). We used propensity adjusted, multivariable Cox proportional hazards models to assess the association of HT on mortality at 72-hour and within the first 2 weeks of arrival at a TTC; these multivariable analyses were stratified by distance (miles) between NTC and TTC: 21-90, and greater than 90. 

Results: Mean distance between NTC and TTC was greater for HT patients, 96.7 miles versus 69.9 miles for GT. A higher proportion of patients among the HT group had an ISS of 16 or higher (24.6% vs 10.9%), an initial SBP < 90 mmHg (7.3% vs 2.8%), and GCS < 10 (12.5% vs 3.7%) than the GT group. HT was associated with significantly decreased 72-hour mortality (HR 0.65, 95%CI 0.48-0.90) for patients transferred from a NTC <90 miles from the TTC. No association was seen for patients transferred more than 90 miles to the TTC. No significant association of HT and 2-week mortality was seen at any distance from the TTC. 

Conclusions: Only for patients transferred from an NTC <90 miles from the receiving TTC was HT associated with a significantly decreased hazard of mortality in the first 72 hours. Many HT patients, especially from the most distant NTCs, had minor injuries and normal vital signs at both the NTC and TTC suggesting the decision to use HT for these patients was resource-driven rather than clinical.

Fatal head and neck injuries in military underbody blast casualties

Sarah K Stewart, A P Pearce, Jon C Clasper

J R Army Med Corps 2019 Feb;165(1):18-21 

Abstract

Introduction: Death as a consequence of underbody blast (UBB) can most commonly be attributed to central nervous system injury. UBB may be considered a form of tertiary blast injury but is at a higher rate and somewhat more predictable than injury caused by more classical forms of tertiary injury. Recent studies have focused on the transmission of axial load through the cervical spine with clinically relevant injury caused by resultant compression and flexion.

This paper seeks to clarify the pattern of head and neck injuries in fatal UBB incidents using a pragmatic anatomical classification.

Methods: This retrospective study investigated fatal UBB incidents in UK triservice members during recent operations in Afghanistan and Iraq. Head and neck injuries were classified by anatomical site into: skull vault fractures, parenchymal brain injuries, base of skull fractures, brain stem injuries and cervical spine fractures. Incidence of all injuries and of each injury type in isolation was compared.

Results: 129 fatalities as a consequence of UBB were identified of whom 94 sustained head or neck injuries. 87 casualties had injuries amenable to analysis. Parenchymal brain injuries (75%) occurred most commonly followed by skull vault (55%) and base of skull fractures (32%).

Cervical spine fractures occurred in only 18% of casualties. 62% of casualties had multiple sites of injury with only one casualty sustaining an isolated cervical spine fracture.

Conclusion: Improvement of UBB survivability requires the understanding of fatal injury mechanisms. Although previous biomechanical studies have concentrated on the effect of axial load transmission and resultant injury to the cervical spine, our work demonstrates that cervical spine injuries are of limited clinical relevance for UBB survivability and that research should focus on severe brain injury secondary to direct head impact.

Systematic approach to delivering prolonged field care in a prehospital care environment

Michael Smith, K Johnston, R Withnall

BMJ Mil Health 2020 Feb 27;jramc-2019-001224 

Background: This article describes a novel patient care algorithm which provides a Role 1 (R1) medic with a structured approach to delivering prolonged field care (PFC) in a resource-limited environment. PFC is a vital component of the operational patient care pathway providing the continuum of care from completion of a primary survey to the delivery to hospital care. Future operational environments are likely to have more fragile or extended lines of communication, potentially delaying evacuation to hospital care. This delay may lead to increases in patient morbidity and mortality. Effective PFC offers an opportunity to improve patient outcomes and help mitigate against this risk.

Methods: An initial prototype model of a PFC care process was developed using existing hospital-based guidance. A series of medical and trauma vignettes and best available evidence were used to refine the algorithm.

Results: The algorithm has been designed be used in conjunction with patient specific clinical guidance making the approach generalisable for all patient groups. For UK military, clinical guidance is provided by clinical guidelines for operations. The algorithm can be downloaded into a convenient format to be used on mobile devices or printed as an aide memoire.

Combat thoracic surgery in Iraq and Afghanistan: 2002-2016

Caryn A Stern , Zsolt T Stockinger, Jennifer M Gurney

J Trauma Acute Care Surg 2020 Sep;89(3):551-557 

Background: Thoracic surgery constitutes 2.5% of surgical procedures performed in theater, but the skills required are increasingly foreign to military surgeons. This study examines thoracic surgical workload in Iraq and Afghanistan to help define surgical training gaps.

Methods: Retrospective analysis of Department of Defense Trauma Registry for all role 2 (R2) (forward surgical) and role 3 (R3) (theater) military facilities, from January 2002 to May 2016. The 95 thoracic surgical International Classification of Diseases-9th Rev.-Clinical Modification procedure codes were grouped into 10 categories based on anatomy or endoscopy. Select groups were further stratified by type of definitive procedure. Procedure groupings were determined and adjudicated by surgeon subject matter experts. Data analysis used Stata Version 15 (College Station, TX).

Results: Of the total procedures, 5,301 were classified as thoracic surgical procedures and were included in the present study. The majority of thoracic surgical procedures (4,645 [87.6%]) were recorded as being performed at R3 medical treatment facilities (MTFs). The thoracic surgical procedures groups with the largest proportions were: bronchoscopy (39.1%), thoracotomy (16.9%), diaphragm (15.6%), and lung (11.4%). The most common lung procedure subgroup, aside from not otherwise specified, was segmentectomy (28.8%). The R3 MTFs recorded nearly five times the number of lung procedures compared with R2 MTFs; with R3 MTFs recording more than eight times the number of lobectomies compared with R2 MTFs.

Thoracic workload was variable over the 15-year study period.

Conclusion: Thoracic surgical skills are necessary in the deployed environment to manage combat-related injuries. Given the current trends in training and specialization, development and sustainment of thoracic surgical skills is challenging in the deployed US trauma system and likely for other nations, and humanitarian surgical care as well. Current training and practice paradigms pose both training and sustainment challenges for surgeons who deploy to a combat zone.

Level of evidence: Therapeutic/Care Management IV.

Successful ventilation of two animals with a single ventilator: individualized shared ventilator setup in an in vivo model

 Michiel Stiers, Tom Bleeser, Matthias Mergeay, Hannah Pinson, Luc Janssen, Tom Schepens 

Crit Care. 2020 Aug 27;24(1):523 

No abstract available

Pilot Study of a Novel Swine Model for Controlling Junctional Hemorrhage Using the iTClamp in Conjunction With Hemostatic Agents

Sean M Stuart, Gregory Zarow, Alexandra Walchak, Julie McLean, Paul Roszko

Mil Med 2019 Mar 1;184(Suppl 1):367-373 

Abstract

Exsanguinating hemorrhage is a primary cause of battlefield death. The iTClamp is a relatively new device (FDA approval in 2013) that takes a different approach to hemorrhage control by applying mechanism wound closure. However, no previous studies have explored the feasibility of utilizing the iTClamp in conjunction with hemostatic packing. To fill this important gap in the literature, a novel swine model was developed, and a total of 12 trials were performed using QuikClot Combat Gauze or XSTAT sponges in conjunction with the iTClamp to treat arterial injuries through 5 cm or 10 cm skin incisions in the groin, axilla, or neck. First-attempt application success rate, application time, and blood loss were recorded. Hemostasis was achieved on all wounds, though reapplication was required in one Combat Gauze and three XSTAT applications. Application averaged ~50% slower for Combat Gauze (M = 41 seconds, 95%CI: 22-32 seconds) than for XSTAT (M = 27 seconds, 95%CI: 35-47 seconds). XSTAT application was faster than Combat Gauze for each wound location and size. The 10 cm wounds took ~10 seconds (36%) longer to close (M = 27 seconds, 95%CI: 35-47 seconds) than the 5 cm wounds (M = 27 seconds, 95%CI: 35-47 seconds). Blood loss was similar for Combat Gauze (M = 51 mL, 95%CI: 25-76 mL) and XSTAT (M = 60 mL, 95%CI: 30-90 mL). Blood loss was roughly twice as great for 10 cm wounds (M = 73 mL, 95%CI: 47-100 mL) than for 5 cm wounds (M = 38 mL, 95%CI: 18-57 mL). This pilot study supports the feasibility of a novel model for testing the iTClamp in conjunction with hemostatic packing towards controlling junctional hemorrhage.

Acute Kidney Injury in Active Wars and Other Man-Made Disasters

Mehmet Sukru Sever, Raymond Vanholder, Norbert Lameire 

Semin Nephrol. 2020 Jul;40(4):341-353 

Abstract 

Acute kidney injury (AKI) is frequent during wars and other man-made disasters, and contributes significantly to the overall death toll. War-related AKI may develop as a result of polytrauma, traumatic bleeding and hypovolemia, chemical and airborne toxin exposure, and crush syndrome. Thus, prerenal, intrinsic renal, or postrenal AKI may develop at the battlefield, in field hospitals, or tertiary care centers, resulting not only from traumatic, but also nontraumatic, etiologies. The prognosis usually is unfavorable because of systemic and polytrauma-related complications and suboptimal therapeutic interventions. Measures for decreasing the risk of AKI include making preparations for foreseeable disasters, and early management of polytrauma-related complications, hypovolemia, and other pathogenetic mechanisms. Transporting casualties initially to field hospitals, and afterward to higher-level health care facilities at the earliest convenience, is critical. Other man-made disasters also may cause AKI; however, the number of patients is mostly lower and treatment possibilities are broader than in war. If there is no alternative other than prolonged field care, the medical community must be prepared to offer health care and even perform dialysis in austere conditions, which in that case, is the only option to decrease the death toll resulting from AKI.

Human performance research for military operations in extreme cold environments

Wendy Sullivan-Kwantes, Francois Haman, Boris R M Kingma, Svein Martini, Emilie Gautier-Wong, Kong Y Chen, Karl E Friedl 

J Sci Med Sport. 2020 Dec 15;S1440-2440(20)30832-X. doi: 10.1016/j.jsams.2020.11.010. Online ahead of print. 

Objectives: Soldier performance in the Arctic depends on planning and training, protective equipment, and human physiological limits. The purpose of this review was to highlight the span of current research on enhancing soldier effectiveness in extreme cold and austere environments. 

Methods: The practices of seasoned soldiers who train in the Arctic and cold-dwelling natives inform performance strategies. We provide examples of research and technology that build on these concepts. 

Results: Examples of current performance research include evaluation of equipment and tactics such as the bioenergetics of load carriage over snow in Norwegian exercises; Canadian field monitoring of hand temperatures and freezing cold injuries for better protection of manual dexterity; and Dutch predictive modeling of cold-wet work tolerances. Healthy young men can respond to cold with a substantial thermogenic response based on US and Canadian studies on brown adipose tissue and other mechanisms of non-shivering thermogenesis; the potential advantage of greater fat insulation is offset in obese unfit subjects by a smaller thermogenic response. Current physiological studies are addressing previously unanswered problems of cold acclimation procedures, thermogenic enhancement and regulation, and modulation of sympathetic activation, all of which may further enhance cold survival and expand the performance envelope. 

Conclusion: There is an inseparable behavioral component to soldier performance in the Arctic, and even the best equipment does not benefit soldiers who have not trained in the actual environment. Training inexperienced soldiers to performance limits may be helped with personal monitoring technologies and predictive models.

An Assessment of Pre-deployment Training for Army Nurses and Medics

Mithun R Suresh, Krystal K Valdez-Delgado, Amanda M Staudt, Jennifer D Trevino 1, Elizabeth A Mann-Salinas 2, Christopher A VanFosson 1 

Mil Med. 2020 Oct 3;usaa291. doi: 10.1093/milmed/usaa291. Online ahead of print 

Introduction: Although military nurses and medics have important roles in caring for combat casualties, no standardized pre-deployment training curriculum exists for those in the Army. A large-scale, survey-based evaluation of pre-deployment training would help to understand its current state and identify areas for improvement. The purpose of this study was to survey Army nurses and medics to describe their pre-deployment training. 

Materials and methods: Using the Intelink.gov platform, a web-based survey was sent by e-mail to Army nurses and medics from the active and reserve components who deployed since 2001. The survey consisted of questions asking about pre-deployment training from their most recent deployment experience. Descriptive statistics were used to analyze the results, and free text comments were also captured. 

Results: There were 682 respondents: 246 (36.1%) nurses and 436 (63.9%) medics. Most of the nurses (n = 132, 53.7%) and medics (n = 298, 68.3%) reported that they were evaluated for clinical competency before deployment. Common courses and topics included Tactical Combat Casualty Care, Advanced Cardiac Life Support, cultural awareness, and trauma care. When asked about the quality of their pre-deployment training, most nurses (n = 186; 75.6%) and medics (n = 359; 82.3%) indicated that their training was adequate or better. Nearly all nurses and medics reported being moderately confident or better (nurses n = 225; 91.5% and medics n = 399; 91.5%) and moderately prepared or better (nurses n = 223; 90.7% and medics n = 404; 92.7%) in their ability to provide combat casualty care. When asked if they participated in a team-based evaluation of clinical competence, many nurses (n = 121, 49.2%) and medics (n = 180, 41.3%) reported not attending a team training program. 

Conclusions: Most nurse and medic respondents were evaluated for clinical competency before deployment, and they attended a variety of courses that covered many topics. Importantly, most nurses and medics were satisfied with the quality of their training, and they felt confident and prepared to provide care. Although these are encouraging findings, they must be interpreted within the context of self-report, survey-based assessments, and the low response rate. Although these limitations and weaknesses of our study limit the generalizability of our results, this study attempts to address a critical knowledge gap regarding pre-deployment training of military nurses and medics. Our results may be used as a basis for conducting additional studies to gather more information on the state of pre-deployment training for nurses and medics. These studies will hopefully have a higher response rate and better quantify how many individuals received any form of pre-deployment training. Additionally, our recommendations regarding pre-deployment training that we derived from the study results may be helpful to military leadership.

 

Anatomic injury patterns in combat casualties treated by forward surgical teams

Mithun R Suresh, Krystal K Valdez-Delgado, Christopher A VanFosson, Jennifer D Trevino, Elizabeth A Mann-Salinas, Stacy A Shackelford, Amanda M Staudt

J Trauma Acute Care Surg 2020 Aug;89(2S Suppl 2):S231-S236 

Background: Role 2 forward surgical teams provide damage-control resuscitation and surgery for life- and limb-threatening injuries. These teams have limited resources and personnel, so understanding the anatomic injury patterns seen by these teams is vital for providing adequate training and preparation prior to deployment. The objective of this study was to describe the spectrum of injuries treated at Role 2 facilities in Afghanistan.

Methods: Using Department of Defense Trauma Registry data, a retrospective, secondary data analysis was conducted. Eligible patients were all battle or non-battle-injured casualties treated by Role 2 forward surgical teams in Afghanistan from October 2005 to June 2018. Abbreviated Injury Scale (AIS) 2005 codes were used to classify each injury and Injury Severity Score (ISS) was calculated for each patient. Patients with multiple trauma were defined as patients with an AIS severity code >2 in at least two ISS body regions.

Results: The data set included 10,383 eligible patients with 45,225 diagnosis entries (range, 1- 27 diagnoses per patient). The largest number of injuries occurred in the lower extremity/pelvis/buttocks (23.9%). Most injuries were categorized as minor (39.4%) or moderate (38.8%) in AIS severity, while the largest number of injuries categorized as severe or worse occurred in the head (13.5%). Among head injuries, 1,872 injuries were associated with a cerebral concussion or diffuse axonal injury, including 50.6% of those injuries being associated with a loss of consciousness. There were 1,224 patients with multiple trauma, and the majority had an injury to the extremities/pelvic girdle (58.2%). Additionally, 3.7% of all eligible patients and 10.5% of all patients with multiple trauma did not survive to Role 2 discharge.

Conclusion: The injury patterns seen in recent conflicts and demonstrated by this study may assist military medical leaders and planners to optimize forward surgical care in future environments, on a larger scale, and utilizing less resources.

Considerations for Development of Exposure Limits for Chemicals Encountered During Aircraft Operation

Lisa M Sweeney, Jeffery M Gearhart, Darrin K Ott, Heather A Pangburn

Mil Med 2020 Jan 7;185(Suppl 1):390-395 

Abstract

Background: Military aircrews' health status is critical to their mission readiness, as they perform physically and cognitively demanding tasks in nontraditional work environments. Research Objectives: Our objective is to develop a broad operational risk assessment framework and demonstrate its applicability to health risks to aircrews because of airborne chemical exposure, considering stressors such as heat and exertion.

Methods: Extrapolation of generic exposure standards to military aviation-specific conditions can include computation of risk-relevant internal dosimetry estimates by incorporating changes in breathing patterns and blood flow distribution because of aspects of the in-flight environment. We provide an example of the effects of exertion on peak blood concentrations of 1,2,4- trimethylbenzene computed using a physiologically based pharmacokinetic model.

Results: Existing published collections on the effects of flight-related stressors on breathing patterns and blood flow address only a limited number of stressors. Although data exist that can be used to develop operational exposure limits specific to military aircrew activities, efforts to integrate this information in specific chemical assessments have been limited.

Conclusions: Efforts to develop operational exposure limits would benefit from guidance on how to make use of existing assessments and expanded databases of the impact of environmental stressors on adult human physiology.

Terrorist threat: Creating a nationwide damage control training program for non-trauma care providers

Astrée Swiech, Gaël de Rocquigny, Thibault Martinez, Gwion Loarer, Sylvain Vico, Jérôme Planchon, Arnaud Le Goff, Kilian Bertho, Clément Derkenne, Stéphane Travers, Brice Malgras, Christophe Martinaud, Cyril Carfantan, Stéphane Gaudry, Mathieu Boutonnet, Pierre Pasquier 

Anaesth Crit Care Pain Med. 2020 Feb;39(1):59-64 

Introduction: The current terrorist threat challenges nations to train numerous non-trauma care providers with different backgrounds in damage control (DC) strategies. The purpose of this work was to propose a specific DC training program. 

Methods: A Task Force of 16 civilian and military physicians met for a 24-hour session, to propose the construction of a DC training program for non-specialised caregivers. 

Results: Existing DC training programs are heterogeneous, mainly theoretical and almost only for physicians. A program entitled Damage Control for Terrorist Attack Victims (DC-TAV) was then proposed. Identified training targets were care providers from prehospital and hospital staffs, with no experience in trauma care. The training objectives were the improvement of individual and collective skills in managing terrorist attacks casualties. The tools selected for training concerned e-learning on a dedicated digital teaching platform (including a core section of four modules with types and mechanisms of injury, basic DC techniques, triage, organisation of emergency medical response and two complementary modules for doctors with DC resuscitation including remote transfusion and DC surgery), hands-on workshops with procedural simulation and full-scale simulation exercises, technical (tourniquets, haemostatic gauzes, needle thoracostomy, chest tube drainage, management of airway, coniotomy) and non-technical (leadership, communication, coordination and triage, decision-making, appropriate use of resources) skills. Finally, an evaluation of the DC-TAV program was planned. 

Conclusions: The DC-TAV program is an ambitious, civilian-military, nationwide and long-term program, based on a harmonised standard of care and including multidimensional training. Further studies are required to assess its efficacy.

How To Maintain The Readiness of Forward Deployed Caregivers

Matthew D Tadlock, Matthew Carr, Joseph Diaz, Peter Rhee, Jeremy W Cannon, Brian J Eastridge, Margaret M Morgan, Erik Brink, Stacy A Shackelford, Jennifer M Gurney, Jay A Johannigman, Anne G Rizzo, M Margaret Knudson, Joseph M Galante 

J Trauma Acute Care Surg. 2020 Dec 31;Publish Ahead of Print. doi: 10.1097/TA.0000000000003054. Online ahead of print 

Abstract 

The Military Health System is currently in the midst of a sea change as Military Treatment Facilities transition to Defense Health Agency governance. During this time of transition, the measurement and sustainment of forward deployed caregiver readiness is undergoing appropriate and much needed scrutiny. Recently, the American Association for the Surgery of Trauma assembled an expert panel to examine forward deployed caregiver readiness, identify gaps, and propose potential solutions. A qualitative theme array analysis of the session was performed, and three readiness themes were identified including: 1) defining readiness, 2) measuring readiness, and 3) maintaining and replenishing readiness. This article focuses on the various readiness gaps, solutions and areas of controversy identified.

Comparison of three methods for teaching mechanical ventilation in an emergency setting to sixth-year medical students: a randomized trial

Fernando Sabia Tallo, Letícia Sandre Vendrame, André Luciano Baitello 

Rev Assoc Med Bras (1992). 2020 Oct;66(10):1409-1413 

Objective: To determine if there are significant differences between the tutorial, simulation, or clinical-case-based discussion teaching methods regarding the transmission of medical knowledge on mechanical ventilation. 

Methods: A randomized, multicenter, open-label controlled trial was carried out using 3 teaching methods on mechanical ventilation: clinical-case-based discussion, simulation, and online tutorial. Voluntary students of the sixth year of medical school from 11 medical colleges answered a validated questionnaire on knowledge about mechanical ventilation for medical students before, immediately after, and 6 months after in-person training consisting of 20 multiple-choice questions, and 5 questions about the participants' demographic profile. 

Results: Immediately after the test there was no difference between the scores in the simulation and clinical case groups,[15,06 vs 14,63] whereas, after some time, there was a significant difference in retention between the case-based and simulation groups, with the score in the simulation group 1.46 [1.31; 1.64] times higher than the score of the case group (p-value < 0.001). In the multivariate analysis, an individual who had received more than 4 hours of information showed an increase of 20.0% [09.0%; 33.0%] in the score (p-value = 0.001). 

Conclusions: Our results indicate that, in comparison with other forms of training, simulation in mechanical ventilation provides long-lasting knowledge in the medium term. Further studies are needed to improve the designing and evaluation of training that provides minimal mechanical ventilation skills.

Needle Aspiration Versus Closed Thoracostomy in the Treatment of Spontaneous Pneumothorax: A Meta-analysis

Jixiang Tan, Hong Chen, Jin He, Lin Zhao

Lung 2020 Apr;198(2):333-344 

Abstract

Purpose: To compare the effectiveness and safety between needle aspiration (NA) and closed thoracostomy (CT) method in adult spontaneous pneumothorax (SP) patients and to explore the most effective and safe protocol by using meta-analysis method.

Materials and methods: This study was based on Cochrane methodology for conducting meta- analysis. Only randomized controlled trials were eligible for this study. The participants were adults who had SP. The Review Manager Database was used to analyze selected studies.

Results: Nine RCTs involving 665 patients were included. Although the initial success rate of CT was higher, the two groups were not statistically significant (RR 0.87 [95% CI 0.76-1.00]; p = 0.05). Compared the NA group, the use of CT method to treat SP significantly increased complications (RR 0.17 [95% CI 0.06-0.45]; p = 0.0003) and operation rate (RR 0.57 [95% CI 0.35-0.95]; p = 0.03). There was no significant difference in the 1-week success rate, admitted rate, 3-month recurrence rate, 1-year recurrence rate, and recurrence time between the two groups. Subgroup analysis of primary spontaneous pneumothorax (PSP) and secondary spontaneous pneumothorax (SSP) patients showed that the initial success rate of the CT method was higher than NA group (RR 0.74 [95% CI 0.60-0.92]; p = 0.007).

Conclusions: For the treatment of SP, NA method could significantly decrease complication rate, operation rate, as well as hospital stay length, compared with the CT method. Subgroup analysis indicated that the use of CT method in SSP and PSP patients might increase the initial success rate.

Lefamulin vs moxifloxacin for community-acquired bacterial pneumonia

Hung-Jen Tang, Jui-Hsiang Wang, Chih-Cheng Lai 

Medicine (Baltimore). 2020 Jul 17;99(29):e21223 

Abstract 

Lefamulin is a novel pleuromutilin antibiotic with potent in vitro activity against key community-acquired bacterial pneumonia (CABP) pathogens. However, the clinical efficacy and safety of lefamulin for treating CABP remains unclear.An integrated analysis of 2 phase III trials investigating the clinical efficacy and safety of lefamulin vs moxifloxacin in the treatment of CABP was conducted.A total of 1289 patients (lefamulin group: 646 and moxifloxacin group: 643) were included in this analysis. The early clinical response rate was 89.3% and 90.5% among lefamulin and moxifloxacin group, respectively. Lefamulin was noninferior to moxifloxacin (89.3% vs 90.5%, RR: 0.99, 95% CI: 0.95-1.02, I = 0%). In terms of clinical response at test of cure, no significant difference was observed between the lefamulin and moxifloxacin groups (for modified intention to treat population, RR: 0.98, 95% CI: 0.94-1.02, I = 0%; for clinically evaluable population, RR: 0.96, 95% CI: 0.93-1.00, I = 0%). In the subgroup analysis, the early clinical response rate at early clinical assessment and clinical response rate at test of cure of lefamulin was similar to that of moxifloxacin across different subgpopulations and all baseline CABP pathogens. Lefamulin was associated with a similar risk of adverse events as moxifloxacin.Clinical efficacy and tolerability for lefamulin in the treatment of CABP were similar to those for moxifloxacin.

Time to Hemorrhage Control in a Hybrid ER System: Is it Time to Change?

Danielle Tatum, Juan Duchesne, Bruno Pereira, Bryan Cotton, Mansoor Khan, Megan Brenner, Paula Ferrada, Tal Hörer, David Kauvar, Andrew Kirkpatrick, Carlos Ordonez, Artai Pirouzram, Derek Roberts

Shock 2020 Mar 19;Online ahead of print

Time to hemorrhage control is critical, as mortality in patients with severe hemorrhage that arrive to trauma centers with sign of life remains over 40%. Prompt identification and management of severe hemorrhage is paramount to reducing mortality. In traditional US trauma systems, the early hospital course of a severely hemorrhaging patient typically proceeds from the trauma resuscitation bay to the operating room or angiography suite with a potential stop for radiological imaging. This protracted journey can prove fatal as it consumes valuable minutes. In contrast to the current US system is a newly developed and increasingly adopted system in Japan called the hybrid emergency room system (HERS). The hybrid ER is equipped to allow resuscitation, imaging, and damage control intervention to occur in the ER without the need to transport the patient to a subsequent destination. The HERS is relatively new and remains restricted to a small number of institutions, limiting the ability to robustly examine impact(s) on patient outcomes. Even if proven to yield superior outcomes, there are significant obstacles to adopting the HERS in the US. Challenges such as the high cost of building and implementing a HER system, return on investment, and the significant differences between the US and Japan in terms of physician training, trauma center, and reimbursement schemes may render the hybrid ER system to be unfeasible in most current trauma centers. Barriers aside, the Japanese hybrid ER system remains the most novel recent advancement in the quest to reduce potentially preventable mortality from hemorrhage.

How emergency physicians choose chest tube size for traumatic pneumothorax or hemothorax: a comparison between 28Fr and smaller tube

Takafumi Terada, Tetsuro Nishimura, Kenichiro Uchida, Naohiro Hagawa, Maiko Esaki, Yasumitsu Mizobata

Nagoya J Med Sci 2020 Feb;82(1):59-68 

Most traumatic pneumothoraxes and hemothoraxes can be managed non-operatively by means of chest tube thoracostomy. This study aimed to investigate how emergency physicians choose chest tube size and whether chest tube size affects patient outcome. We reviewed medical charts of patients who underwent chest tube insertion for chest trauma within 24 hours of admission in this retrospective, single-institution study. Patient characteristics, inserted tube size, risk of additional tube, and complications were evaluated. Eighty-six chest tubes were placed in 64 patients. Sixty-seven tubes were placed initially, and 19 additionally, which was significantly smaller than the initial tube. Initial tube size was 28 Fr in 38 and <28 Fr in 28 patients. Indications were pneumothorax (n=24), hemothorax (n=7), and hemopneumothorax (n=36). Initial tube size was not related to sex, BMI, BSA, indication, ISS, RTS, chest AIS, or respiratory status. An additional tube was placed in the same thoracic cavity for residual pneumothorax (n=13), hemothorax (n=1), hemopneumothorax (n=1), and inappropriate extrapleural placement (n=3). Risk of additional tube placement was not significantly different depending on tube size. No additional tube was placed for tube occlusion or surgical intervention for residual clotted hemothorax. Emergency physicians did not choose tube size depending on patient sex, body size, or situation. Even with a <28 Fr tube placed in chest trauma patients, the risk of residual hemo/pneumothorax and tube occlusion did not increase, and drainage was effective.

Comparison of two point of care whole blood coagulation analysis devices and conventional coagulation tests as a predicting tool of perioperative bleeding in adult cardiac surgery-a pilot prospective observational study in Japan

Rui Terada, Toshiyuki Ikeda, Yoshiteru Mori, Sho Yamazaki, Kosuke Kashiwabara, Haruo Yamauchi, Minoru Ono, Yoshitsugu Yamada, Hitoshi Okazaki

Transfusion 2019 Nov;59(11):3525-3535 

Abstract

Background: It is widely accepted that Point-of Care Test (PoCT) devices are useful in the detection of coagulopathies in situations of massive bleeding such as major cardiac surgery. These devices contribute to the reduction of blood transfusion. However, their implementation remains limited in Japan because of their cost and lack of health insurance support.

Study design and methods: Conventional coagulation tests and thromboelastography (TEG)/Sonoclot values were measured in 50 consecutive cardiac surgery cases. Clinical background information such as operative procedures was obtained from electronic medical records, and the theoretical perioperative total blood loss was calculated by measuring the hemoglobin content and total red blood cell transfusion volume. The correlation between perioperative total blood loss and the measured laboratory values or clinical parameters was evaluated by a multivariate linear regression analysis. The risk factors of the total amount of platelet transfusion and postoperative drain bleeding volume were similarly evaluated.

Results: No significant association between the estimated perioperative total blood loss (eTBL) and the laboratory measurements including conventional coagulation tests, TEG and Sonoclot was observed. On the other hand, postoperative drain bleeding volume was significantly associated with postoperative Sonoclot CR (p = 0.039) as well as preoperative use of oral anticoagulants and cell saver treated blood volume. Platelet transfusion amount was significantly associated with post-CBP PF and time to peak value of Sonoclot (p = 0.014 and 0.001, respectively).

Conclusion: Sonoclot measurements may be useful to estimate the risks of postoperative bleeding and platelet transfusion in cardiac surgeries in Japan.

Pre-hospital blood transfusion - an ESA survey of European practice

Karl-Christian Thies, Anatolij Truhlář, Damian Keene, Jochen Hinkelbein, Kurt Rützler, Luca Brazzi, Benoît Vivien 

Scand J Trauma Resusc Emerg Med. 2020 Aug 14;28(1):79 

Background: Blood products are a lifesaving commodity in the treatment of major trauma. Although there is little evidence for use of pre-hospital blood products (PHBP) in seriously injured patients, an increasing number of emergency medical services have started using PHBP for treatment of major haemorrhage. The primary aim of this survey was to establish the degree of prehospital blood product use throughout Europe and discover main indications. The secondary aim was to evaluate opinions about PHBP and also the experience and the personal views of its users. 

Methods: The subcommittee for Critical Emergency Medicine of the European Society of Anaesthesiology (ESA) held an online survey of European Helicopter Emergency Services (HEMS) and all French Services d'Aide Médicale Urgente (SAMU) regions. It contained 13 questions both open and multiple-choice about the frequency transfusions are carried out, the PHBP used and the perceived benefit. The survey was distributed to the corresponding HEMS leads in 14 European countries. 

Results: In total there were 172 valid responses; overall 48% of all respondents have prehospital access to packed red cells, 22% to fresh plasma and 14% use lyophilised plasma. Besides blood product administration, 94% of all services use tranexamic acid. Sixty five percent of all replies came from French and from German services (37 and 28% respectively). PHBP were mainly used for trauma related emergencies. France has the highest uptake of use of blood products at 89%, whereas the rate in Germany was far lower at 6%. Fifty five percent of the service leads felt that PHBP are beneficial, and even lifesaving in individual cases despite being needed infrequently. 

Conclusions: We found remarkable dissimilarities in practice between the different European countries. Even if there is not an absolute consensus amongst providers on the benefit of PHBP, the majority feel they are beneficial. The difference in practice is possibly related to the perceived lack of evidence on prehospital blood transfusion. We suggest to include the use of PHBP in trauma registries in order to consolidate the existing evidence.

Multidisciplinary prehospital critical care

Joshua M Tobin, Cliff Reid, Brian J Burns 

J Trauma Acute Care Surg. 2020 Dec;89(6):e188-e189 

No abstract available

Experience in an Urban Level 1 Trauma Center With Tranexamic Acid in Pediatric Trauma: A Retrospective Chart Review

Julie M ThomsonHanh H HuynhHolly M DroneJessica L JantzerAlbert K TsaiJon T Jancik

J Intensive Care Med 2020 Feb; Online ahead of print.

Abstract 

Background: Evidence for tranexamic acid (TXA) in the pharmacologic management of trauma is largely derived from data in adults. Guidance on the use of TXA in pediatric patients comes from studies evaluating its use in cardiac and orthopedic surgery. There is minimal data describing TXA safety and efficacy in pediatric trauma. The purpose of this study is to describe the use of TXA in the management of pediatric trauma and to evaluate its efficacy and safety end points. 

Methods: This retrospective, observational analysis of pediatric trauma admissions at Hennepin County Medical Center from August 2011 to March 2019 compares patients who did and did not receive TXA. The primary end point is survival to hospital discharge. Secondary end points include surgical intervention, transfusion requirements, length of stay, thrombosis, and TXA dose administered. 

Results: There were 48 patients aged ≤16 years identified for inclusion using a massive transfusion protocol order. Twenty-nine (60%) patients received TXA. Baseline characteristics and results are presented as median (interquartile range) unless otherwise specified, with statistical significance defined as P < .05. Patients receiving TXA were more likely to be older, but there was no difference in injury type or Injury Severity Score at baseline. There was no difference in survival to discharge or thrombosis. Patients who did not receive TXA had numerically more frequent surgical intervention and longer length of stay, but these did not reach significance. 

Conclusions: TXA was utilized in 60% of pediatric trauma admissions at a single level 1 trauma center, more commonly in older patients. Although limited by observational design, we found patients receiving TXA had no difference in mortality or thrombosis.

Ketamine Administration in Prehospital Combat Injured Patients With Traumatic Brain Injury: A 10-Year Report of Survival

Allee C Torres, Vikhyat S Bebarta, Michael D April, Joseph K Maddry, Paco S Herson, Emma K Bebarta, Steven Schauer 

Cureus. 2020 Jul 17;12(7):e9248. doi: 10.7759/cureus.9248 

Abstract

Background The Tactical Combat Casualty Care (TCCC) guidelines recommend ketamine as the primary battlefield analgesic in the setting of moderate-to-severe pain and hemodynamic compromise. However, despite recent studies failing to support the association between ketamine and worse outcomes in head trauma, TCCC guidelines state that ketamine may worsen severe traumatic brain injury. We compared mortality outcomes following head trauma sustained in a combat setting between ketamine recipients and non-recipients. Methods This is a secondary analysis of previously published data in the Department of Defense Trauma Registry from January 2007 to August 2016. We isolated patients with an abbreviated injury scale of 3 or greater for the head body region. We compared mortality between prehospital ketamine recipients and non-recipients. Results Our initial search yielded 28,222 patients, of which 4,183 met the inclusion criteria: 209 were ketamine-recipients and 3,974 were non-recipients. The ketamine group had a higher percentage injured by explosives (59.81% vs. 53.57%, p<0.001) and gunshot wounds (28.71% vs. 22.07%, p<0.001) and were more frequently located in Afghanistan (100% vs. 68.0%, p<0.001). The ketamine group had higher rates of tourniquet application (24.4% vs. 8.5%, p<0.001) and had lower survival proportion (75.1% alive vs. 83.0%, p=0.003). All differences were significant. On univariable analysis, the ketamine group had worse odds of survival with (OR: 0.62; 95%CI: 0.45-0.86). When controlling for the presence of an airway intervention and mechanism of injury, the finding was non-significant (OR: 1.09; 95% CI: 0.76-1.55). Conclusions In our prehospital combat study, after controlling for confounders, we found no association between administration of prehospital ketamine and worse survival outcomes for casualties with head injuries. However, despite the lack of difference in overall survival noted, those who received ketamine and died had a higher risk ratio for time to death.

Pragmatic Strategy Empowering Paramedics to Assess Low-Risk Trauma Patients With the Canadian C-Spine Rule and Selectively Transport Them Without Immobilization: Protocol for a Stepped-Wedge Cluster Randomized Trial

Christian Vaillancourt, Manya Charette, Monica Taljaard, Kednapa Thavorn, Elizabeth Hall, Brent McLeod, Dean Fergusson, Jamie Brehaut, Ian Graham, Lisa Calder, Tim Ramsay, Peter Tugwell, Peter Kelly, Sheldon Cheskes, Refik Saskin, Amy Plint, Martin Osmond, Colin Macarthur, Sharon Straus, Paula Rochon, Denis Prud'homme, Simone Dahrouge, Susan Marlin, Ian G Stiell 

JMIR Res Protoc. 2020 Jun 1;9(6):e16966. doi: 10.2196/16966 

Background: Each year, half a million patients with a potential neck (c-spine) injury are transported to Ontario emergency departments (EDs). Less than 1.0% (1/100) of these patients have a neck bone fracture. Even less (1/200, 0.5%) have a spinal cord injury or nerve damage. Currently, paramedics transport all trauma victims (with or without an injury) by ambulance using a backboard, cervical collar, and head immobilizers. Importantly, prolonged immobilization is often unnecessary; it causes patient discomfort and pain, decreases community access to paramedics, contributes to ED crowding, and is very costly. We therefore developed the Canadian C-Spine Rule (CCR) for alert and stable trauma patients. This decision rule helps ED physicians and triage nurses to safely and selectively remove immobilization, without x-rays and missed injury. We successfully taught Ottawa paramedics to use the CCR in the field in a single-center study. 

Objective: This study aimed to improve patient care and health system efficiency and outcomes by allowing paramedics to assess eligible low-risk trauma patients with the CCR and selectively transport them without immobilization to the ED. 

Methods: We propose a pragmatic stepped-wedge cluster randomized design with health economic evaluation, designed collaboratively with knowledge users. Our 36-month study will consist of a 12-month setup and training period (year 1), followed by the stepped-wedge trial (year 2) and a 12-month period for study completion, analyses, and knowledge translation. A total of 12 Ontario paramedic services of various sizes distributed across the province will be randomly allocated to one of three sequences. Paramedic services in each sequence will cross from the control condition (usual care) to the intervention condition (CCR implementation) at intervals of 3 months until all communities have crossed to the intervention. Data will be collected on all eligible patients in each paramedic service for a total duration of 12 months. A major strength of our design is that each community will have implemented the CCR by the end of the study. 

Results: Interim results are expected in December 2019 and final results in 2020. If this multicenter trial is successful, we expect the Ontario Ministry of Health will recommend that paramedics evaluate all eligible patients with the CCR in the Province of Ontario. 

Conclusions: We conservatively estimate that in Ontario, more than 60% of all eligible trauma patients (300,000 annually) could be transported safely and comfortably, without c-spine immobilization devices. This will significantly reduce patient pain and discomfort, paramedic intervention times, and ED length of stay, thereby improving access to paramedics and ED care. This could be achieved rapidly and with lower health care costs compared with current practices (possible cost saving of Can $36 [US $25] per immobilization or Can $10,656,000 [US $7,335,231] per year).

Dilemma of crystalloid resuscitation in non-exsanguinating polytrauma: what is too much?

Karlijn van Wessem, Falco Hietbrink, Luke Leenen 

Trauma Surg Acute Care Open. 2020 Oct 28;5(1):e000593 

Background: Aggressive crystalloid resuscitation increases morbidity and mortality in exsanguinating patients. Polytrauma patients with severe tissue injury and subsequent inflammatory response without major blood loss also need resuscitation. This study investigated crystalloid and blood product resuscitation in non-exsanguinating polytrauma patients and studied possible adverse outcomes. 

Methods: A 6.5-year prospective cohort study included consecutive trauma patients admitted to a Level 1 Trauma Center intensive care unit (ICU) who survived 48 hours. Demographics, physiologic and resuscitation parameters in first 24 hours, Denver Multiple Organ Failure scores, adult respiratory distress syndrome (ARDS) data and infectious complications were prospectively collected. Patients were divided in 5 L crystalloid volume subgroups (0-5, 5-10, 10-15 and >15 L) to make clinically relevant comparisons. Data are presented as median (IQR); p value <0.05 was considered significant. 

Results: 367 patients (70% men) were included with median age of 46 (28-61) years, median Injury Severity Score was 29 (22-35) and 95% sustained blunt injuries. 17% developed multiple organ dysfunction syndrome (MODS), 4% ARDS and 14% died. Increasing injury severity, acidosis and coagulopathy were associated with more crystalloid administration. Increasing crystalloid volumes were associated with more blood products, increased ventilator days, ICU length of stay, hospital length of stay, MODS, infectious complications and mortality rates. Urgent laparotomy was found to be the most important independent predictor for crystalloid resuscitation in multinominal regression analysis. Further, fresh frozen plasma (FFP) <8 hours was less likely to be administered in patients >5 L compared with the group 0-5 L. With increasing crystalloid volume, the adjusted odds of MODS, ARDS and infectious complications increased 3-4-fold, although not statistically significant. Mortality increased 6-fold in patients who received >15 L crystalloids (p=0.03). 

Discussion: Polytrauma patients received large amounts of crystalloids with few FFPs <24 hours. In patients with <10 L crystalloids, <24-hour mortality and MODS rates were not influenced by crystalloid resuscitation. Mortality increased 6-fold in patients who received >15 L crystalloids ≤24 hours. Efforts should be made to balance resuscitation with modest crystalloids and sufficient amount of FFPs.

Prehospital Use of Ketamine in Mountain Rescue: A Survey of Emergency Physicians of a Single-Center Alpine Helicopter-Based Emergency Service

Katia Vanolli, Olivier Hugli, David Eidenbenz, Marc R Suter, Mathieu Pasquier 

Wilderness Environ Med. 2020 Dec;31(4):385-393 

Introduction: Although ketamine use in emergency medicine is widespread, studies investigating prehospital use are scarce. Our goal was to assess the self-reported modalities of ketamine use, knowledge of contraindications, and occurrence of adverse events associated with its use by physicians through a prospective online survey. 

Methods: The survey was administered to physicians working for Air-Glaciers, a Swiss alpine helicopter-based emergency service, and was available between September 24 and November 23, 2018. We enrolled 39 participants (participation rate of 87%) in our study and collected data regarding their characteristics, methods of ketamine use, knowledge of contraindications, and encountered side effects linked to the administration of ketamine. We also included a clinical scenario to investigate an analgesic strategy. 

Results: Ketamine was considered safe and judged irreplaceable by most physicians. The main reason for ketamine use was acute analgesia during painful procedures, such as manipulation of femur fractures. The doses of ketamine administered with or without fentanyl ranged from 0.2 to 0.7 mg·kg-1 intravenously. Most physicians reported using fentanyl and midazolam along with ketamine. The median dose of midazolam was 2 (interquartile range 1-2) mg for a 70-kg adult. Monitoring and oxygen administration were used infrequently. Hallucinations were the most common adverse events. Knowledge of ketamine contraindications was poor. 

Conclusions: Ketamine use was reported by mountain rescue physicians to be safe and useful for acute analgesia. Most physicians use fentanyl and midazolam along with ketamine. Adverse neuropsychiatric events were rare. Knowledge regarding contraindications to the administration of ketamine should be improved.

Prehospital administration of blood products: experiences from a Finnish physician-staffed helicopter emergency medical service

Pauli Vuorinen, Joonas-Eemeli Kiili, Piritta Setälä, Antti Kämäräinen, Sanna Hoppu 

BMC Emerg Med. 2020 Jul 7;20(1):55 

Background: Massive infusions of crystalloids into bleeding hypotensive patients can worsen the outcome. Military experience suggests avoiding crystalloids using early damage control resuscitation with blood components in out of hospital setting. Civilian emergency medical services have since followed this idea. We describe our red blood cell protocol in helicopter emergency medical services (HEMS) and initial experience with prehospital blood products from the first 3 years after implementation. 

Methods: We performed an observational study of patients attended by the HEMS unit between 2015 and 2018 to whom packed red blood cells, freeze-dried plasma, or both were transfused. The Student's two-sided T-test was used to compare vitals in prehospital phase with those at the hospital's emergency department. A p-value < 0.05 was considered significant. 

Results: Altogether, 62 patients received prehospital transfusions. Of those, 48 (77%) were trauma patients and most (n = 39, 81%) suffered blunt trauma. The transfusion began at a median of 33 (IQR 21-47) minutes before hospital arrival. Median systolic blood pressure showed an increase from 90 mmHg (IQR 75-111 mmHg) to 107 mmHg (IQR 80-124 mmHg; P < 0.026) during the prehospital phase. Four units of red blood cells were handled incorrectly when unused red blood cells were returned and required disposal during a three-year period. There were no reported adverse effects from prehospital transfusions. 

Conclusion: We treated two patients per month with prehospital blood products. A prehospital physician-staffed HEMS unit carrying blood products is a feasible and safe method to start transfusion roughly 30 min before arrival to the hospital.

Effects of MOPP Gear on SAM Medical Junctional Tourniquet Application: A Prospective, Randomized Control Trial

Eric M Wagner, Jason F Naylor, Brian J Ahern, Brett C Gendron, Michael D April, Steven G Schauer 

Mil Med. 2020 Sep 18;185(9-10):e1810-e1816 

Introduction: Hemorrhage is the leading cause of preventable death on the battlefield, and hemostasis is particularly challenging to achieve at junctional sites such as the axillary or inguinal regions. Mission-oriented protective posture (MOPP) gear, as worn most recently in Syria to guard against chemical weapons, can make the performance of technical skills more challenging still. The objective of this study was to evaluate how wearing MOPP gear affects the application time of the SAM Medical Junctional Tourniquet (SJT) by U.S. Army combat medics. 

Materials and methods: We conducted a prospective, randomized control trial evaluating time for SJT application between participants wearing MOPP versus those not wearing MOPP. Secondary outcomes included SJT application success rate and participant appraisal of SJT application difficulty assessed with five-point Likert items, between groups. Participants placed SJTs on robotic simulation mannequins with a penetrating inguinal injury. 

Results: In April 2019, we enrolled 49 combat medics. Most participants were male (77.5%), had a median age of 25 (interquartile range 23-28), and in the grade of E4 or less (63.3%). Mean SJT application times in seconds were higher among those wearing MOPP versus those who were not (223.1 versus 167.2; 95% confidence interval for difference in means 5.293, 106.374; P = 0.03). Participants wearing MOPP had a less successful application rate overall, but this difference was not statistically significant (64.3% versus 81.0%, P = 0.34). Compared to participants not wearing MOPP, those wearing MOPP agreed that SJT application was difficult (4 versus 3, P = 0.03), what they were wearing affected SJT application (4 versus 2, P = 0.01), and it was difficult to use their hands during SJT application (4 versus 1, P < 0.001). 

Conclusions: Wearing military MOPP gear significantly prolongs the amount of time required for combat medics to apply an SJT on a simulated casualty with a penetrating inguinal injury. This study highlights the importance of incorporating MOPP gear into medical training scenarios to improve skills competency while wearing these protective garments.

Complications from Needle Thoracostomy: Penetration of the Myocardium

Arielle Thomas,  K Hope Wilkinson, Kevin Young, Timothy Lenz, Jillian Theobald

Prehosp Emerg Care 2020 Jun 10;1-3 

We report a rare but serious complication of needle thoracostomy, penetration of the myocardium. Needle thoracostomy is typically performed in the prehospital setting or upon arrival in the emergency department for suspected tension pneumothorax. Needle decompression is generally taught and done anteriorly, in the 2nd intercostal space on the midclavicular line (MCL). An alternative approach is laterally, along the anterior axillary line (AAL) in the 4th intercostal space. Our case supports prior literature that the anterior MCL location has a low rate of efficacy to decompress the chest, as well as a high rate of complications. We recommend performing needle decompression laterally at the AAL whether in the field or in the emergency department.

Early Identification of Acute Traumatic Coagulopathy Using Clinical Prediction Tools: A Systematic Review

Sophie Thorn, Helge Güting, Marc Maegele, Russell L Gruen, Biswadev Mitra

Medicina (Kaunas) 2019 Sep 28;55(10):653 

Background and objectives: Prompt identification of patients with acute traumatic coagulopathy (ATC) is necessary to expedite appropriate treatment. An early clinical prediction tool that does not require laboratory testing is a convenient way to estimate risk. Prediction models have been developed, but none are in widespread use. This systematic review aimed to identify and assess accuracy of prediction tools for ATC.

Materials and Methods: A search of OVID Medline and Embase was performed for articles published between January 1998 and February 2018. We searched for prognostic and predictive studies of coagulopathy in adult trauma patients. Studies that described stand-alone predictive or associated factors were excluded. Studies describing prediction of laboratory- diagnosed ATC were extracted. Performance of these tools was described.

Results: Six studies were identified describing four different ATC prediction tools. The COAST score uses five prehospital variables (blood pressure, temperature, chest decompression, vehicular entrapment and abdominal injury) and performed with 60% sensitivity and 96% specificity to identify an International Normalised Ratio (INR) of >1.5 on an Australian single centre cohort. TICCS predicted an INR of >1.3 in a small Belgian cohort with 100% sensitivity and 96% specificity based on admissions to resuscitation rooms, blood pressure and injury distribution but performed with an Area under the Receiver Operating Characteristic (AUROC) curve of 0.700 on a German trauma registry validation. Prediction of Acute Coagulopathy of Trauma (PACT) was developed in USA using six weighted variables (shock index, age, mechanism of injury, Glasgow Coma Scale, cardiopulmonary resuscitation, intubation) and predicted an INR of >1.5 with 73.1% sensitivity and 73.8% specificity. The Bayesian network model is an artificial intelligence system that predicted a prothrombin time ratio of >1.2 based on 14 clinical variables with 90% sensitivity and 92% specificity.

Conclusions: The search for ATC prediction models yielded four scoring systems. While there is some potential to be implemented effectively in clinical practice, none have been sufficiently externally validated to demonstrate associations with patient outcomes. These tools remain useful for research purposes to identify populations at risk of ATC.

A comprehensive review of topical hemostatic agents: The good, the bad, and the novel

Allison J Tompeck, Aniq Ur Reham Gajdhar, Matthew Dowling, Steven B Johnson, Philip S Barie, Robert J Winchell, David King, Thomas M Scalea, L D Britt, Mayur Narayan

J Trauma Acute Care Surg. 2020 Jan;88(1):e1-e21 

Uncontrolled exsanguination remains the leading cause of death for trauma patients, many of whom die in the pre-hospital setting. Without expedient intervention, trauma-associated hemorrhage induces a host of systemic responses and acute coagulopathy of trauma. For this reason, health care providers and prehospital personal face the challenge of swift and effective hemorrhage control. The utilization of adjuncts to facilitate hemostasis was first recorded in 1886. Commercially available products haves since expanded to include topical hemostats, surgical sealants, and adhesives. The ideal product balances efficacy, with safety practicality and cost-effectiveness. This review of hemostasis provides a guide for successful implementation and simultaneously highlights future opportunities.

Use of a Digital Cognitive Aid in the Early Management of Simulated War Wounds in a Combat Environment, a Randomized Trial

Michael Truchot, Baptiste Balança, Pierre François Wey, Karim Tazarourte, François Lecomte, Arnaud Le Goff, Simon Leigh-Smith, Jean Jacques Lehot, Thomas Rimmele, Jean Christophe Cejka

Mil Med 2020 Aug 14;185(7-8):e1077-e1082

Introduction: The French army has implemented an algorithm based on the acronym "MARCHE RYAN," each letter standing for a key action to complete in order to help first care providers during emergency casualty care. On the battlefield, the risk of error is increased, and the use of cognitive aids (CAs) might be helpful to avoid distraction. We investigated the effect of using a digital CA (MAX, for Medical Assistance eXpert) by combat casualty care providers on their technical and nontechnical performances during the early management of simulated war wounds, compared to their memory and training alone.

Materials and methods: We conducted a randomized, controlled, unblinded study between July 2016 and February 2017. This study was approved by the Ethics Committee of the Ethical Board of Desgenettes Army Training Hospital (14.06.2017 n°385) and was registered on clinicaltrials.gov (NCT03483727). It took place during medicalization training in hostile environment ("MEDICHOS") in Chamonix Mont-Blanc and in the first aid training center in La Valbonne military base (France). Each participant had to deal with two different scenarios, one with MAX (MAX+) and the other without (MAX-). Scenarios were held using either high-fidelity patient simulators or actors as wounded patients. The primary outcome was participants' technical performance rated as their adherence to the MARCHE RYAN procedure (maximum 100%). The secondary outcome was the nontechnical performance according to the Ottawa crisis resource management Global Rating Scale (maximum 42).

Results: Technical performance was significantly higher in the MAX+ scenarios (70.60 IQR [63.70-73.56] than in the MAX- scenarios (56.25 IQR [52.88-62.09], p = 0.002). The Ottawa scores were significantly higher in the MAX+ scenarios (31.50 IQR [29.50-33.75]) than in the MAX- scenarios (29.50 IQR [24.50-32.00], p = 0.031).

Conclusions: The use of a digital CA by combat casualty care providers improved technical and nontechnical performances during field training of simulated crises. Following recommendations on the design and use of CA, regular team training would improve fluidity in the use and acceptance of an aid, by a highly drilled professional corporation with a strong culture of leadership. Digital CA should be tested at a larger scale in order to validate their contribution to real combat casualty care.

Prehospital Vital Signs Accurately Predict Initial Emergency Department Vital Signs

Marc D Trust, Morgan Schellenberg, Subarna Biswas, Kenji Inaba, Vincent Cheng, Zachary Warriner, Bryan E Love, Demetrios Demetriades

Prehosp Disaster Med 2020 Jun;35(3):254-259 

Introduction: Prehospital vital signs are used to triage trauma patients to mobilize appropriate resources and personnel prior to patient arrival in the emergency department (ED). Due to inherent challenges in obtaining prehospital vital signs, concerns exist regarding their accuracy and ability to predict first ED vitals.

Hypothesis/problem: The objective of this study was to determine the correlation between prehospital and initial ED vitals among patients meeting criteria for highest levels of trauma team activation (TTA). The hypothesis was that in a medical system with short transport times, prehospital and first ED vital signs would correlate well.

Methods: Patients meeting criteria for highest levels of TTA at a Level I trauma center (2008- 2018) were included. Those with absent or missing prehospital vital signs were excluded.

Demographics, injury data, and prehospital and first ED vital signs were abstracted. Prehospital and initial ED vital signs were compared using Bland-Altman intraclass correlation coefficients (ICC) with good agreement as >0.60; fair as 0.40-0.60; and poor as <0.40).

Results: After exclusions, 15,320 patients were included. Mean age was 39 years (range 0- 105) and 11,622 patients (76%) were male. Mechanism of injury was blunt in 79% (n = 12,041) and mortality was three percent (n = 513). Mean transport time was 21 minutes (range 0-1,439). Prehospital and first ED vital signs demonstrated good agreement for Glasgow Coma Scale (GCS) score (ICC 0.79; 95% CI, 0.77-0.79); fair agreement for heart rate (HR; ICC 0.59; 95% CI, 0.56-0.61) and systolic blood pressure (SBP; ICC 0.48; 95% CI, 0.46-0.49); and poor agreement for pulse pressure (PP; ICC 0.32; 95% CI, 0.30-0.33) and respiratory rate (RR; ICC 0.13; 95% CI, 0.11-0.15).

Conclusion: Despite challenges in prehospital assessments, field GCS, SBP, and HR correlate well with first ED vital signs. The data show that these prehospital measurements accurately predict initial ED vitals in an urban setting with short transport times. The generalizability of these data to settings with longer transport times is unknown.

Prehospital definitive airway is not associated with improved survival in trauma patients

Avishai M Tsur 1, Roy Nadler, Nir Tsur, Alex Sorkin, Tarif Bader, Avi Benov, Elon Glassberg, Jacob Chen

J Trauma Acute Care Surg 2020 Aug;89(2S Suppl 2):S237-S241 

Background: The American College of Surgeons and the National Association of Emergency Medical Technicians advise securing a definitive airway if there is any doubt about the trauma patient's ability to maintain airway integrity. The objective of this study was to investigate the association between a success in securing a definitive airway in the prehospital setting and survival among trauma patients, in which the provider deemed a definitive airway was necessary.

Methods: The study included all trauma patients recorded in the Israel Defense Forces Trauma Registry between the years 2006 and 2018 for whom a prehospital attempt of securing a definitive airway was documented. The successful definitive airway group was defined by explicit documentation of success in either endotracheal intubation or cricothyrotomy. Logistic regression was performed to determine the association between success in securing a definitive airway and survival.

Results: A total of 566 (3.6%) trauma patients underwent attempts to secure a definitive airway (successful in 425 patients and unsuccessful in 141). Prehospital survival rates were similar (77.6% vs. 78.0%, p = 0.928) between the groups. Whether the definitive airway was successful did not affect the rates of prehospital survival, neither before (odds ratio, 0.98; 95% confidence interval, 0.61-1.54) nor after adjustment for the other factors (odds ratio, 0.91; 95% confidence interval, 0.55-1.46).

Conclusion: This study was unable to find an association between a successful definitive airway in the prehospital setting and survival, even after adjustment for injury characteristics and in multiple models. Furthermore, survival rates were high among trauma patients in which the provider deemed a definitive airway as necessary yet failed in securing one. These results suggest that the liberal use of these invasive airway procedures in the prehospital setting should be reconsidered.

The Israel Defense Forces Trauma Registry: 22 years of point-of-injury data

Avishai M Tsur, Roy Nadler, Ari M Lipsky, Diana Levi, Tarif Bader, Avi Benov, Elon Glassberg, Jacob Chen

J Trauma Acute Care Surg 2020 Aug;89(2S Suppl 2):S32-S38 

Background: Trauma is the leading cause of death among casualties between 1 and 44 years. A large proportion of trauma deaths occurs even before arriving at a medical facility. The paucity of prehospital data is a major reason for the lagging development of prehospital trauma care research. This study aims to describe the Israel Defense Forces Prehopistal Trauma Registry, the steps taken to improve data collection and quality, the resulting trends, and the registry's contribution to policymaking.

Methods: This study explores the quantity and quality of point of injury and prehospital data in the registry between the years 1997 and 2018. We assessed the number of recorded casualties per year, casualties characteristics, and documentation variables in the registry, with a specific focus on documentation of vital signs throughout the years.

Results: Overall, 17,905 casualties were recorded. Most casualties were young males (88.6%)- military personnel (52.7%), Syrian refugees (16.2%), Israeli civilians (11.5%), and Palestinians (9.0%). The median number of annual records from 2006 onward was significantly higher compared with before 2006 (1,000 [IQR, 792-1,470] vs. 142 [IQR, 129-156]). Between 2010 and 2018, documentation rate increased in all vital signs investigated including heart rate (56.3% vs. 1.0%), level of consciousness (55.1% vs. 0.3%), respiratory rate (51.8% vs. 0.3%), blood oxygen saturation (50.0% vs. 1.0%), Glasgow Coma Scale (48.2% vs. 0.4%), systolic blood pressure (45.7% vs. 0.8%), and pain (19.1% vs. 0.5%).

Conclusion: Point of injury and prehospital documentation are rare yet essential for ongoing improvement of combat casualty care. The Israel Defense Forces Trauma Registry is one of the largest and oldest prehospital computerized military trauma registries in the world. This study shows a major improvement in the quantity and then in the quality of prehospital documentation throughout the years that affected guidelines and policy. Further work will focus on improving data completeness and accuracy.

Pre-hospital emergency anaesthesia in the United Kingdom: an observational cohort study

Jake Turner, Sebastian Bourn, James Raitt, Erica Ley, Matthew O'Meara, Pre-Hospital Trainee Operated research Network study investigators

Br J Anaesth 2020 May;124(5):579-584 

Background: Up to one in eight trauma patients arrive at a hospital with a partially or completely obstructed airway. The UK National Institute for health and Care Excellence (NICE) practice guidelines recommend that trauma patients requiring anaesthesia for definitive airway management receive this care within 45 min of an emergency call, preferably at the incident scene. How frequently this target is achieved remains unclear. We assessed the recorded time to pre-hospital emergency anaesthesia after trauma across UK helicopter emergency medical service (HEMS) units.

Methods: We retrospectively recorded time to pre-hospital emergency anaesthesia across all 20 eligible UK HEMS units (comprising 52 enhanced care teams) from April 1, 2017 to March 31, 2018. Times recorded for emergency notification, dispatch, arrival, and neuromuscular blocking agent administration were analysed.

Results: HEMS undertook 1755 pre-hospital emergency anaesthetics for trauma across the UK during the study period. There were 1176/1755 (67%) episodes undertaken by helicopter response teams during daylight hours. The median time to pre-hospital emergency anaesthesia was 55 min (inter-quartile range: 45-70); anaesthesia within 45 min of the initial emergency call was achieved in 25% cases. Delayed dispatch time (>9 min) was associated with fewer patients receiving pre-hospital anaesthesia within 45 min (odds ratio: 7.7 [95% confidence intervals: 5.8-

10.1]; P<0.0001).

Conclusions: The time to achieve pre-hospital emergency anaesthesia by UK HEMS frequently exceeds the recommended 45 min target. Reducing the time to dispatch of emergency medical teams may impact on the delivery of pre-hospital emergency anaesthesia.

Systematic review with meta-analysis: the efficacy of tranexamic acid in upper gastrointestinal bleeding

Erica Twum-Barimah, Ibtihal Abdelgadir, Morris Gordon, Anthony K Akobeng

Aliment Pharmacol Ther 2020 Jun;51(11):1004-1013 

Background: Upper gastrointestinal bleeding is a common medical emergency associated with substantial mortality. Tranexamic acid may be effective for reducing mortality in upper gastrointestinal bleeding.

Aim: To examine the effects of tranexamic acid in upper gastrointestinal bleeding by systematic review and meta-analysis.

Methods: We searched PubMed, EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials (CENTRAL) and other relevant websites for randomised controlled trials investigating the effect of tranexamic acid published from inception to December 10, 2019. The primary outcome of interest was mortality. Estimates of effect were pooled with a random effects model. Quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach.

Results: The search identified 1572 citations. Eleven trials comprising 2076 patients were eligible for inclusion. Of these, 10 trials (2013 patients) compared tranexamic acid with placebo. Risk of death was significantly reduced in patients who received tranexamic acid compared with those who received placebo (RR 0.59, 95% CI 0.43-0.82, P = 0.001) with no significant heterogeneity noted among studies (I2 = 0%, P = 0.81). The GRADE assessment rated the quality of the evidence for mortality as moderate due to risk of bias. There were no statistically significant differences between tranexamic acid and placebo for the prevention of re-bleeding, need for surgical interventions, need for blood transfusions or frequency of thromboembolic events.

Conclusions: Moderate-quality evidence shows that tranexamic acid is superior to placebo for the reduction in mortality in patients with upper gastrointestinal bleeding. While our findings lend further support to the use of tranexamic acid for treating patients with upper gastrointestinal bleeding, additional higher-quality trials are needed.

Validation of an evaluation instrument for responders in tactical casualty care simulations

Maria Del Carmen Usero-Pérez, Maria Lourdes Jiménez-Rodríguez, Alexandra González- Aguña, Valentín González-Alonso, Luis Orbañanos-Peiro, Jose María Santamaría-García, Jorge Luís Gómez-González

Rev Lat Am Enfermagem 2020 Apr 17;28:e3251 

Objective: to construct and validate a tool for the evaluation of responders in tactical casualty care simulations.

Method: three rubrics for the application of a tourniquet, an emergency bandage and haemostatic agents recommended by the Hartford Consensus were developed and validated. Validity and reliability were studied. Validation was performed by 4 experts in the field and 36 nursing participants who were selected through convenience sampling. Three rubrics with 8 items were evaluated (except for the application of an emergency bandage, for which 7 items were evaluated). Each simulation was evaluated by 3 experts.

Results: an excellent score was obtained for the correlation index for the 3 simulations and 2 levels that were evaluated (competent and expert). The mean score for the application of a tourniquet was 0.897, the mean score for the application of an emergency bandage was 0.982, and the mean score for the application of topical haemostats was 0.805.

Conclusion: this instrument for the evaluation of nurses in tactical casualty care simulations is considered useful, valid and reliable for training in a prehospital setting for both professionals who lack experience in tactical casualty care and those who are considered to be experts.

Management of mild traumatic brain injury

Anne van Gils, Jon Stone, Killian Welch, Louise R Davidson, Dean Kerslake, Dave Caesar, Laura McWhirter, Alan Carson

Pract Neurol 2020 May;20(3):213-221 

Mild traumatic brain injury (TBI) is common and associated with a range of diffuse, non-specific symptoms including headache, nausea, dizziness, fatigue, hypersomnolence, attentional difficulties, photosensitivity and phonosensitivity, irritability and depersonalisation. Although these symptoms usually resolve within 3 months, 5%-15% of patients are left with chronic symptoms. We argue that simply labelling such symptoms as 'postconcussional' is of little benefit to patients. Instead, we suggest that detailed assessment, including investigation, both of the severity of the 'mild' injury and of the individual symptom syndromes, should be used to tailor a rehabilitative approach to symptoms. To complement such an approach, we have developed a self-help website for patients with mild TBI, based on neurorehabilitative and cognitive behavioural therapy principles, offering information, tips and tools to guide recovery: www.headinjurysymptoms.org.

Development and validation of a novel prediction model to identify patients in need of specialized trauma care during field triage: design and rationale of the GOAT study

Rogier van der Sluijs, Thomas P A Debray, Martijn Poeze, Loek P H Leenen, Mark van Heijl

Diagn Progn Res 2019 Jun 20;3:12 

Background: Adequate field triage of trauma patients is crucial to transport patients to the right hospital. Mistriage and subsequent interhospital transfers should be minimized to reduce avoidable mortality, life-long disabilities, and costs. Availability of a prehospital triage tool may help to identify patients in need of specialized trauma care and to determine the optimal transportation destination.

Methods: The GOAT (Gradient Boosted Trauma Triage) study is a prospective, multi-site, cross-sectional diagnostic study. Patients transported by at least five ground Emergency Medical Services to any receiving hospital within the Netherlands are eligible for inclusion. The reference standards for the need of specialized trauma care are an Injury Severity Score ≥ 16 and early critical resource use, which will both be assessed by trauma registrars after the final diagnosis is made. Variable selection will be based on ease of use in practice and clinical expertise. A gradient boosting decision tree algorithm will be used to develop the prediction model. Model accuracy will be assessed in terms of discrimination (c-statistic) and calibration (intercept, slope, and plot) on individual participant's data from each participating cluster (i.e., Emergency Medical Service) through internal-external cross-validation. A reference model will be externally validated on each cluster as well. The resulting model statistics will be investigated, compared, and summarized through an individual participant's data meta-analysis.

Discussion: The GOAT study protocol describes the development of a new prediction model for identifying patients in need of specialized trauma care. The aim is to attain acceptable undertriage rates and to minimize mortality rates and life-long disabilities.

Pre-hospital transfusion of red blood cells. Part 1: A scoping review of current practice and transfusion triggers

Elisabeth C van Turenhout, Sebastiaan M Bossers, Stephan A Loer, Georgios F Giannakopoulos, Lothar A Schwarte, Patrick Schober

Transfus Med 2020 Apr;30(2):86-105 

Objectives: The primary aim of this scoping review is to describe the current use of pre-hospital transfusion of red blood cells (PHTRBC) and to evaluate criteria used to initiate PHTRBC. The effects on patients' outcomes will be reviewed in Part 2.

Background: Haemorrhage is a preventable cause of death in trauma patients, and transfusion of red blood cells is increasingly used by Emergency Medical Services (EMS) for damage control resuscitation. However, there are no guidelines and little consensus on when to initiate PHTRBC.

Methods: PubMed and Web of Science were searched through January 2019; 71 articles were included.

Results: Transfusion triggers vary widely and involve vital signs, clinical signs of poor tissue perfusion, point of care measurements and pre-hospital ultrasound imaging. In particular, hypotension (most often defined as systolic blood pressure ≤ 90 mmHg), tachycardia (most often defined as heart rate ≥ 120/min), clinical signs of poor perfusion (eg, prolonged capillary refill time or changes in mental status) and injury type (ie, penetrating wounds) are common pre- hospital transfusion triggers.

Conclusions: PHTRBC is increasingly used by Emergency Medical Services, but guidelines on when to initiate transfusion are lacking. We identified the most commonly used transfusion criteria, and these findings may provide the basis for consensus-based pre-hospital transfusion protocols.

Dilemma of crystalloid resuscitation in non-exsanguinating polytrauma: what is too much?

Karlijn van Wessem, Falco Hietbrink, Luke Leenen

Trauma Surg Acute Care Open. 2020 Oct 28;5(1):e000593 

Background: Aggressive crystalloid resuscitation increases morbidity and mortality in exsanguinating patients. Polytrauma patients with severe tissue injury and subsequent inflammatory response without major blood loss also need resuscitation. This study investigated crystalloid and blood product resuscitation in non-exsanguinating polytrauma patients and studied possible adverse outcomes.

Methods: A 6.5-year prospective cohort study included consecutive trauma patients admitted to a Level 1 Trauma Center intensive care unit (ICU) who survived 48 hours. Demographics, physiologic and resuscitation parameters in first 24 hours, Denver Multiple Organ Failure scores, adult respiratory distress syndrome (ARDS) data and infectious complications were prospectively collected. Patients were divided in 5 L crystalloid volume subgroups (0-5, 5-10, 10-15 and >15 L) to make clinically relevant comparisons. Data are presented as median (IQR); p value <0.05 was considered significant.

Results: 367 patients (70% men) were included with median age of 46 (28-61) years, median Injury Severity Score was 29 (22-35) and 95% sustained blunt injuries. 17% developed multiple organ dysfunction syndrome (MODS), 4% ARDS and 14% died. Increasing injury severity, acidosis and coagulopathy were associated with more crystalloid administration. Increasing crystalloid volumes were associated with more blood products, increased ventilator days, ICU length of stay, hospital length of stay, MODS, infectious complications and mortality rates. Urgent laparotomy was found to be the most important independent predictor for crystalloid resuscitation in multinominal regression analysis. Further, fresh frozen plasma (FFP) <8 hours was less likely to be administered in patients >5 L compared with the group 0-5 L. With increasing crystalloid volume, the adjusted odds of MODS, ARDS and infectious complications increased 3-4-fold, although not statistically significant. Mortality increased 6-fold in patients who received >15 L crystalloids (p=0.03).

Discussion: Polytrauma patients received large amounts of crystalloids with few FFPs <24 hours. In patients with <10 L crystalloids, <24-hour mortality and MODS rates were not influenced by crystalloid resuscitation. Mortality increased 6-fold in patients who received >15 L crystalloids ≤24 hours. Efforts should be made to balance resuscitation with modest crystalloids and sufficient amount of FFPs.

Prehospital Use of Ketamine in Mountain Rescue: A Survey of Emergency Physicians of a Single-Center Alpine Helicopter-Based Emergency Service

Katia Vanolli, Olivier Hugli, David Eidenbenz, Marc R Suter, Mathieu Pasquier

Wilderness Environ Med. 2020 Dec;31(4):385-393 

Introduction: Although ketamine use in emergency medicine is widespread, studies investigating prehospital use are scarce. Our goal was to assess the self-reported modalities of ketamine use, knowledge of contraindications, and occurrence of adverse events associated with its use by physicians through a prospective online survey.

Methods: The survey was administered to physicians working for Air-Glaciers, a Swiss alpine helicopter-based emergency service, and was available between September 24 and November 23, 2018. We enrolled 39 participants (participation rate of 87%) in our study and collected data regarding their characteristics, methods of ketamine use, knowledge of contraindications, and encountered side effects linked to the administration of ketamine. We also included a clinical scenario to investigate an analgesic strategy.

Results: Ketamine was considered safe and judged irreplaceable by most physicians. The main reason for ketamine use was acute analgesia during painful procedures, such as manipulation of femur fractures. The doses of ketamine administered with or without fentanyl ranged from 0.2 to 0.7 mg·kg-1 intravenously. Most physicians reported using fentanyl and midazolam along with ketamine. The median dose of midazolam was 2 (interquartile range 1-2) mg for a 70-kg adult. Monitoring and oxygen administration were used infrequently. Hallucinations were the most common adverse events. Knowledge of ketamine contraindications was poor.

Conclusions: Ketamine use was reported by mountain rescue physicians to be safe and useful for acute analgesia. Most physicians use fentanyl and midazolam along with ketamine. Adverse neuropsychiatric events were rare. Knowledge regarding contraindications to the administration of ketamine should be improved.

Prehospital trauma care evolution, practice and controversies: need for a review

Mathew Varghese

Int J Inj Contr Saf Promot 2020 Mar;27(1):69-82 

Modern medicine and surgery is historically very recent, and most interventions that are so commonly done in a hospital now are only 60 to 70 years old. Understanding of emergency care of the injured is more recent; however, for the sake of temporal convenience trauma care has become compartmentalized into phases: first aid, bystander care, prehospital care, emergency care, definitive levels of care and rehabilitation. The injured patient's body physiology is changing continuously from the time of the impact at the injury site.. The outcome of trauma is dependent not only on what is done in the prehospital phase but also on hospital care and rehabilitation. Our understanding of the changes and the response to interventions in a trauma patient has been evolving over the years. This paper discusses the need to review recent advances in our understanding of the care process and how we need to improve it and how there is a pressing need to generate valid evidence on what we do in emergency care.

Hypocalcaemia and traumatic coagulopathy: an observational analysis

Mayank Vasudeva, Joseph K Mathew, Mark C Fitzgerald, Zoe Cheung, Biswadev Mitra

Vox Sang 2020 Feb;115(2):189-195 

Abstract

Background and objectives: Haemorrhage-associated calcium loss may lead to disruption of platelet function, intrinsic and extrinsic pathway-mediated haemostasis and cardiac contractility. Among shocked major trauma patients, we aimed to investigate the association between admission hypocalcaemia and adverse outcomes.

Materials and methods: Data were extracted from the Alfred Trauma Registry and the Alfred Applications and Knowledge Management Department for all adult major trauma patients presenting directly from the scene with a shock index ≥1 from 1 July 2014 to 30 June 2018.

Patients with pre-hospital blood transfusion were excluded. Ionized hypocalcaemia was defined as <1·11 mmol/l, and acute traumatic coagulopathy was defined as initial INR >1·5.

Multivariable logistic regression analysis was used to assess the association between admission hypocalcaemia and acute traumatic coagulopathy that was adjusted for Injury Severity Score, initial GCS, bicarbonate and lactate.

Results: There were 226 patients included in final analysis with 113 (50%) patients recording ionized hypocalcaemia on presentation prior to any blood product transfusion. Ionized hypocalcaemia was associated with coagulopathy in patients with shock index ≥1 (adjusted OR 2·9; 95% CI: 1·01-8·3, P = 0·048). Admission ionized hypocalcaemia was also associated with blood transfusion requirement in the first 24 h post-admission in 62·5% of hypocalcaemic patients as compared to 37·5% of normocalcaemic patients (P < 0·001). Admission ionized hypocalcaemia was associated with death at hospital discharge (25·6% among hypocalcaemic patients compared to 15·0% of normocalcaemic patients (P = 0·047)).

Conclusion: Hypocalcaemia was a common finding in shocked trauma patients and was independently associated with acute traumatic coagulopathy. The early, protocolized administration of calcium to trauma patients in haemorrhagic shock warrants further assessment in randomized controlled trials.

Prehospital administration of blood products: experiences from a Finnish physician-staffed helicopter emergency medical service

Pauli Vuorinen, Joonas-Eemeli Kiili, Piritta Setälä, Antti Kämäräinen, Sanna Hoppu 

BMC Emerg Med. 2020 Jul 7;20(1):55 

Background: Massive infusions of crystalloids into bleeding hypotensive patients can worsen the outcome. Military experience suggests avoiding crystalloids using early damage control resuscitation with blood components in out of hospital setting. Civilian emergency medical services have since followed this idea. We describe our red blood cell protocol in helicopter emergency medical services (HEMS) and initial experience with prehospital blood products from the first 3 years after implementation. 

Methods: We performed an observational study of patients attended by the HEMS unit between 2015 and 2018 to whom packed red blood cells, freeze-dried plasma, or both were transfused. The Student's two-sided T-test was used to compare vitals in prehospital phase with those at the hospital's emergency department. A p-value < 0.05 was considered significant. 

Results: Altogether, 62 patients received prehospital transfusions. Of those, 48 (77%) were trauma patients and most (n = 39, 81%) suffered blunt trauma. The transfusion began at a median of 33 (IQR 21-47) minutes before hospital arrival. Median systolic blood pressure showed an increase from 90 mmHg (IQR 75-111 mmHg) to 107 mmHg (IQR 80-124 mmHg; P < 0.026) during the prehospital phase. Four units of red blood cells were handled incorrectly when unused red blood cells were returned and required disposal during a three-year period. There were no reported adverse effects from prehospital transfusions. 

Conclusion: We treated two patients per month with prehospital blood products. A prehospital physician-staffed HEMS unit carrying blood products is a feasible and safe method to start transfusion roughly 30 min before arrival to the hospital.

Effects of MOPP Gear on SAM Medical Junctional Tourniquet Application: A Prospective, Randomized Control Trial

Eric M Wagner, Jason F Naylor, Brian J Ahern, Brett C Gendron, Michael D April, Steven G Schauer 

Mil Med. 2020 Sep 18;185(9-10):e1810-e1816 

Introduction: Hemorrhage is the leading cause of preventable death on the battlefield, and hemostasis is particularly challenging to achieve at junctional sites such as the axillary or inguinal regions. Mission-oriented protective posture (MOPP) gear, as worn most recently in Syria to guard against chemical weapons, can make the performance of technical skills more challenging still. The objective of this study was to evaluate how wearing MOPP gear affects the application time of the SAM Medical Junctional Tourniquet (SJT) by U.S. Army combat medics. 

Materials and methods: We conducted a prospective, randomized control trial evaluating time for SJT application between participants wearing MOPP versus those not wearing MOPP. Secondary outcomes included SJT application success rate and participant appraisal of SJT application difficulty assessed with five-point Likert items, between groups. Participants placed SJTs on robotic simulation mannequins with a penetrating inguinal injury. 

Results: In April 2019, we enrolled 49 combat medics. Most participants were male (77.5%), had a median age of 25 (interquartile range 23-28), and in the grade of E4 or less (63.3%). Mean SJT application times in seconds were higher among those wearing MOPP versus those who were not (223.1 versus 167.2; 95% confidence interval for difference in means 5.293, 106.374; P = 0.03). Participants wearing MOPP had a less successful application rate overall, but this difference was not statistically significant (64.3% versus 81.0%, P = 0.34). Compared to participants not wearing MOPP, those wearing MOPP agreed that SJT application was difficult (4 versus 3, P = 0.03), what they were wearing affected SJT application (4 versus 2, P = 0.01), and it was difficult to use their hands during SJT application (4 versus 1, P < 0.001). 

Conclusions: Wearing military MOPP gear significantly prolongs the amount of time required for combat medics to apply an SJT on a simulated casualty with a penetrating inguinal injury. This study highlights the importance of incorporating MOPP gear into medical training scenarios to improve skills competency while wearing these protective garments.

Contributing factors that influence medication errors in the prehospital paramedic environment: a mixed-method systematic review protocol

Dennis Walker, Clint Moloney, Brendan SueSee, Renee Sharples

BMJ Open 2019 Dec 23;9(12):e034094 

Abstract

Introduction: There is limited reliable research available on medication errors in relation to paramedic practice, with most evidence-based medication safety guidelines based on research in nursing, operating theatre and pharmacy settings. While similarities exist, evidence suggests that the prehospital environment is distinctly different in many aspects. The prevention of errors requires attention to factors from the organisational and regulatory level down to specific tasks and patient characteristics. The evidence available suggests errors may occur in up to 12.76% of medication administrations in some prehospital settings. With multiple sources stating that the errors are under-reported, this represents significant potential for patient harm. This review will seek to identify the factors influencing the occurrence of medication errors by paramedics in the prehospital environment.

Methods and analysis: The review will include qualitative and quantitative studies involving interventions or phenomena regarding medication errors or medication safety relating to paramedics (including emergency medical technicians and other prehospital care providers) within the prehospital environment. A search will be conducted using MEDLINE (Ovid), EBSCOhost Megafile Search, the International Committee of Medical Journal Editors trial registry, Google Scholar and the OpenGrey database to identify studies meeting this inclusion criteria, with initial searches commencing 30 September 2019. Studies selected will undergo assessment of methodological quality, with data to be extracted from all studies irrespective of quality. Each stage of study selection, appraisal and data extraction will be conducted by two reviewers, with a third reviewer deciding any unresolved conflicts. The review will follow a convergent integrated approach, conducting a single qualitative synthesis of qualitative and 'qualitised' quantitative data.

Ethics and dissemination: No ethical approval was required for this review. Findings from this systematic review will be disseminated via publications, reports and conference presentations.

Outcomes of tranexamic acid administration in military trauma patients with intracranial hemorrhage: a cohort study

Patrick F Walker, Joseph D Bozzay, Luke R Johnston, Eric A Elster, Carlos J Rodriguez, Matthew J Bradley

BMC Emerg Med 2020 May 14;20(1):39 

Background: Tranexamic acid (TXA) may be a useful adjunct for military patients with severe traumatic brain injury (TBI). These patients are often treated in austere settings without immediate access to neurosurgical intervention. The purpose of this study was to evaluate any association between TXA use and progression of intracranial hemorrhage (ICH), neurologic outcomes, and venous thromboembolism (VTE) in TBI.

Methods: This was a retrospective cohort study of military casualties from October 2010 to December 2015 who were transferred to a military treatment facility (MTF) in the United States. Data collected included: demographics, types of injuries, initial and interval head computerized tomography (CT) scans, Glasgow Coma Scores (GCS), and six-month Glasgow Outcome Scores (GOS). Results were stratified based on TXA administration, progression of ICH, and VTE.

Results: Of the 687 active duty service members reviewed, 71 patients had ICH (10.3%). Most casualties were injured in a blast (80.3%), with 36 patients (50.7%) sustaining a penetrating TBI. Mean ISS was 28.2 ± 12.3. Nine patients (12.7%) received a massive transfusion within 24 h of injury, and TXA was administered to 14 (19.7%) casualties. Patients that received TXA had lower initial reported GCS (9.2 ± 4.4 vs. 12.5 ± 3.4, p = 0.003), similar discharge GCS (13.3 ±4.0 vs. 13.8 ± 3.2, p = 0.58), and a larger improvement between initial and discharge GCS (3.7± 3.9 vs. 1.3 ± 3.1, p = 0.02). However, there was no difference in mortality (7.1% vs. 7.0%, p = 1.00), progression of ICH (45.5% vs. 14.7%, p = 0.09), frequency of cranial decompression (50.0% vs. 42.1%, p = 0.76), or mean GOS (3.5 ± 0.9 vs. 3.8 ± 1.0, p = 0.13). Patientsadministered TXA had a higher rate of VTE (35.7% vs. 7.0%, p = 0.01). On multivariate analysis, however, TXA was not independently associated with VTE.

Conclusions: Patients that received TXA were associated with an improvement in GCS but not in progression of ICH or GOS. TXA was not independently associated with VTE, although this may be related to a paucity of patients receiving TXA. Decisions about TXA administration in military casualties with ICH should be considered in the context of the availability of neurosurgical intervention as well as severity of extracranial injuries and need for massive transfusion.

Non-invasive sensor technology for prehospital stroke diagnosis: Current status and future directions

Kyle B Walsh

Int J Stroke 2019 Aug;14(6):592-602 

Abstract

Background: The diagnosis of stroke in the prehospital environment is the subject of intense interest and research. There are a number of non-invasive external brain monitoring devices in development that utilize various technologies to function as sensors for stroke and other neurological conditions. Future increased use of one or more of these devices could result in substantial changes in the current processes for stroke diagnosis and treatment, including transportation of stroke patients by emergency medical services.

Aims: The present review will summarize information about 10 stroke sensor devices currently in development, utilizing various forms of technology, and all of which are external, non-invasive brain monitoring devices.

Summary of review: Ten devices are discussed including the technology utilized, the indications for use (stroke and, when relevant, other neurological conditions), the environment(s) indicated for use (with a focus on the prehospital setting), a description of the physical structure of each instrument, and, when available, findings that have been published in peer-reviewed journals or otherwise reported. The review is organized based on the technology utilized by each device, and seven distinct forms were identified: accelerometers, electroencephalography (EEG), microwaves, near-infrared, radiofrequency, transcranial doppler ultrasound, and volumetric impedance phase shift spectroscopy.

Conclusions: Non-invasive external brain monitoring devices are in various stages of development and have promise as stroke sensors in the prehospital setting. Some of the potential applications include to differentiate stroke from non-stroke, ischemic from hemorrhage stroke, and large vessel occlusion (LVO) from non-LVO ischemic stroke. Successful stroke diagnosis prior to hospital arrival could transform the current diagnostic and treatment paradigm for this disease.

A Low-Cost Insertion Trainer for Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA)

Ryan Walsh, Charles Lei, Kenneth H Palm, Ryan J Van Nostrand, Zachary Sletten 

Cureus 2020 Aug 13;12(8):e9729 

Abstract 

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emergency procedure designed to treat non-compressible torso hemorrhage. Because this is a high-acuity low-occurrence event, it is difficult to train providers on the procedure and difficult for trained providers to stay proficient. Our primary objective was to develop a low-cost, high-fidelity teaching model to increase emergency medicine (EM) resident knowledge, confidence, and proficiency in performing REBOA. We utilized readily available materials to allow for ease of replication and cost-effectiveness. The aorta was simulated by a bicycle tire inner tube, and the femoral artery was simulated by natural rubber tubing. Once connected, these simulated vascular structures were threaded through a plastic torso mold and filled with simulated blood. Participants then performed the REBOA procedure with very little time required for reset between participants. After completing the training using our model, participants completed a survey rating aspects of the session on a five-point Likert scale. Participants included 21 EM residents from all levels of training. Participants rated the fidelity of the REBOA insertion trainer very highly (mean = 4.05, SD 0.67) and felt that the training was overall very useful (mean = 4.29, SD 0.56). Comments regarding the model were universally positive. We present a novel low-cost REBOA task trainer that is easy to build, reusable, and portable, and can be utilized either in a hospital or austere training environment.

A natural polymer-based porous sponge with capillary-mimicking microchannels for rapid hemostasis.

Liangyu Wang, Yuanyuan Zhong, Chuntong Qian, Dongzhi Yang, Jun Nie, Guiping Ma 

Acta Biomater. 2020 Sep 15;114:193-205 

Abstract 

Natural polymer materials have attracted great attention in the field of hemostasis because of their wide range of source, nontoxicity, hydrophilicity, and air permeability. In the present study, two natural polymers composed of carboxymethyl chitosan (CMCS) and sodium carboxymethylcellulose (CMCNa) plus γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560) that serves as a crosslinking agent were selected to synthesize a capillary-mimicking composite hemostatic (CCK) sponge with a low density, interconnected microchannel architecture, suitable mechanical strength, high resilience, and ultrastrong liquid absorption capacity. The introduction of a large number of hydrophilic carboxymethyl functional groups and the design of capillary-mimicking structures formed by the ice segregation-induced self-assembly (ISISA) process endowed the CCK sponges with an ultrastrong liquid absorption capacity, which significantly enhanced the hemostatic ability of the materials. Both in vivo and in vitro hemostatic experiments confirmed the potential of the CCK sponges to achieve rapid hemostasis. Additionally, cytotoxicity and hemolysis assays showed that the CCK sponges exhibited good biocompatibility and hemocompatibility. The possible hemostatic mechanism was also discussed in this study. In conclusion, the capillary-mimicking hemostatic sponge exhibits a high potential to induce rapid hemostasis in prehospital emergency and clinical settings. STATEMENT OF SIGNIFICANCE: In the present study, an oriented composite hemostatic (CCK) sponge with a capillary-mimicking structure formed by the ice segregation-induced self-assembly (ISISA) process was designed and used to achieve rapid hemostasis. The unique aligned microchannel structure of the sponge exhibited an ultrastrong capillary-mimicking action and endowed the prepared CCK hemostatic sponge with a strong liquid absorption capacity. By changing the proportion of raw materials, we could modify the unique capillary-mimicking structure with aligned microchannels. Two natural polymer-based materials with abundant hydrophilic groups were chosen to prepare the CCK sponge to fully utilize the characteristics of this structure. The oriented natural polymer-based porous sponge with capillary-mimicking microchannels exhibited a strong hemostatic ability in both in vivo and in vitro tests. The results showed that the CCK sponge with the capillary-mimicking structure has a high potential to achieve rapid hemostasis.

Endotracheal intubation during out-of-hospital cardiac arrest: New insights from recent clinical trials

Henry E Wang, Jonathan R Benger

J Am Coll Emerg Physicians Open. 2019 Dec 16;1(1):24-29 

Abstract 

Airway management is an important intervention during resuscitation of out-of-hospital cardiac arrest (OHCA). Endotracheal intubation is commonly used by emergency medical services paramedics in the advanced airway management of OHCA, but numerous studies question its safety and effectiveness. Furthermore, there is now increasing use of supraglottic airway devices. In this review, we provide an overview of 3 recent randomized clinical trials of advanced airway management (Pragmatic Airway Resuscitation Trial [PART], AIRWAYS-2, and Cardiac Arrest Airway Management [CAAM]) and highlight new information that is available to guide OHCA airway management practices.

Novel 4W (When-Where-What-What) Approach of Training Point-of-Care Ultrasound (POCUS) Application in Resuscitation With High-Fidelity Simulator

Hong Wang, Adam M Uraco, Justin Stover, Nicole Hollis 

Cureus. 2020 Jul 23;12(7):e9353 

Abstract 

Aim Point-of-care ultrasound (POCUS) is a valuable tool in anesthesiology used for evaluating and managing cardiopulmonary pathology. Implications of this modality are extensive. Seamless integration into advanced cardiac life support (ACLS) has potential to improve resuscitation outcomes, and there is growing impetus for its implementation during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. However, it remains underutilized largely due to limited training. We use high-fidelity simulation and a novel 4W approach (when to apply POCUS, where to place the ultrasound probe, what images mean, what to do next) to incorporate this technique into resuscitation training. This study aims to evaluate the efficacy of a novel 4W POCUS approach for training anesthesiology residents in the setting of resuscitation. Methods Our approach teaches learners when and where to implement POCUS, how to interpret their findings, and how to apply these findings in a clinical setting. Learners apply this method in high-fidelity simulation to diagnose and treat cardiopulmonary pathologies. Assessments were administered before and after training to evaluate efficacy. Results Post-test improvements were appreciated across all residency classes (n = 23), with achieved significance of P < 0.001 in the first-year clinical anesthesia class (CA-1) and P = 0.02 in the second-year clinical anesthesia class (CA-2). Performance was further subdivided into five categories: resuscitation integration, lung ultrasound, transthoracic echo, disease recognition, and treatment. Post-test scores also improved in each category, with lung ultrasound being the most significant improvement (P = 0.04). Conclusions Our initial data demonstrate the effectiveness of this approach to POCUS training. Performance is improved and learners are more likely to use POCUS in the future. The application of this method to larger sample sizes is an appropriate next step to demonstrate its utility.

Killed in action (KIA): an analysis of military personnel who died of their injuries before reaching a definitive medical treatment facility in Afghanistan (2004-2014)

Stacey Webster, E B G Barnard, J E Smith, M E R Marsden, C Wright BMJ

Mil Health 2020 Jun 2; Online ahead of print. 

Introduction: The majority of combat deaths occur before arrival at a medical treatment facility but no previous studies have comprehensively examined this phase of care.

Methods: The UK Joint Theatre Trauma Registry was used to identify all UK military personnel who died in Afghanistan (2004-2014). These data were linked to non-medical tactical and operational records to provide an accurate timeline of events. Cause of death was determined from records taken at postmortem review. The primary objective was to report time between injury and death in those killed in action (KIA); secondary objectives included: reporting mortality at key North Atlantic Treaty Organisation timelines (0, 10, 60, 120 min), comparison of temporal lethality for different anatomical injuries and analysing trends in the case fatality rate (CFR).

Results: 2413 UK personnel were injured in Afghanistan from 2004 to 2014; 448 died, with a CFR of 18.6%. 390 (87.1%) of these died prehospital (n=348 KIA, n=42 killed non-enemy action). Complete data were available for n=303 (87.1%) KIA: median Injury Severity Score 75.0 (IQR 55.5-75.0). The predominant mechanisms were improvised explosive device (n=166, 54.8%) and gunshot wound (n=96, 31.7%).In the KIA cohort, the median time to death was 0.0 (IQR 0.0-21.8) min; 173 (57.1%) died immediately (0 min). At 10, 60 and 120 min post injury, 205 (67.7%), 277 (91.4%) and 300 (99.0%) casualties were dead, respectively. Whole body primary injury had the fastest mortality. Overall prehospital CFR improved throughout the period while in-hospital CFR remained constant.

Conclusion: Over two-thirds of KIA deaths occurred within 10 min of injury. Improvement in the CFR in Afghanistan was predominantly in the prehospital phase.

Systematic review of prehospital haemostatic dressings

Matthew Welch, J Barratt, A Peters, C Wright

BMJ Mil Health 2020 Jun;166(3):194-200 

Introduction: Haemorrhage is one of the leading causes of battlefield and prehospital death. Haemostatic dressings are an effective method of limiting the extent of bleeding and are used by military forces extensively. A systematic review was conducted with the aim of collating the evidence on current haemostatic products and to assess whether one product was more effective than others.

Methods: A systematic search and assessment of the literature was conducted using 13 health research databases including MEDLINE and CINAHL, and a grey literature search. Two assessors independently screened the studies for eligibility and quality. English language studies using current-generation haemostatic dressings were included. Surgical studies, studies that did not include survival, initial haemostasis or rebleeding and those investigating products without prehospital potential were excluded.

Results: 232 studies were initially found and, after applying exclusion criteria, 42 were included in the review. These studies included 31 animal studies and 11 clinical studies. The outcomes assessed were subject survival, initial haemostasis and rebleeding. A number of products were shown to be effective in stopping haemorrhage, with Celox, QuikClot Combat Gauze and HemCon being the most commonly used, and with no demonstrable difference in effectiveness.

Conclusions: There was a lack of high-quality clinical evidence with the majority of studies being conducted using a swine haemorrhage model. Iterations of three haemostatic dressings, Celox, HemCon and QuikClot, dominated the studies, probably because of their use by international military forces and all were shown to be effective in the arrest of haemorrhage.

Evaluating tourniquet use in Swedish prehospital care for civilian extremity trauma

Eric Wellme, Victor Mill, Carl Montán

Eur J Trauma Emerg Surg 2020 Apr 29; Online ahead of print. 

Purpose: The use of tourniquet (TQ) is today a well-documented and lifesaving adjunct to control bleeding from extremity trauma in the military setting. Since August 2015, the ambulance services in Stockholm, Sweden are equipped with TQs. The implementation and potential complications related to TQ use have so far not been evaluated. The primary aim of this study was to evaluate the prehospital use of TQ for haemorrhage control in extremity trauma. Possible complications following the use of TQ were analysed.

Methods: A retrospective, descriptive cohort study of extremity haemorrhage for all patients (n= 56) with a documented prehospital use of TQ admitted to the trauma centre at Karolinska University Hospital from 1st August 2015 to 31st December 2017 was conducted. Data regarding TQ use including indication, duration, bleeding volume, complications and definitive injury were analysed.

Results: Out of 63 placements of TQ in 56 patients, TQ stopped the bleeding effectively in 98.2% of the cases and the TQ time varied from 15 to 100 min. The overall complication rate was 30.1%; however, complications possibly related to TQ use were 3.6%. In 16 (28.6%) cases, the TQ were used for a non-life-threating haemorrhage which may have been stopped with direct pressure only.

Conclusion: This study shows TQs to be an effective but overused tool in haemorrhage control. The use of TQ was not associated with any severe complications, implying the safety and effectiveness of the device in the civilian setting if TQ time is kept under 100 min.

Evaluation of the intensity and management of pain before arrival in hospital among patients with suspected hip fractures

Pär Wennberg 1, Margareta Möller 2, Elisabeth Kenne Sarenmalm 3, Johan Herlitz 4

Int Emerg Nurs 2020 Mar;49: Epub 2020 Feb 3. 

Abstract

Background: Pain management needs to be comprehensively investigated in patients with hip fractures, as it represents a fast-growing challenge to emergency care. The purpose of this study was to describe reported pain in patients with suspected hip fractures in a prehospital setting.

Methods: In this observational study, 1,426 patients with a suspected hip fracture were included. Dynamic and static pain were assessed on the arrival of the emergency medical services (EMS) and on hospital admission using the Numerical Rating Scale (NRS), if feasible, and the Behaviour Rating Scale (BRS), if not.

Results: On EMS arrival, the median dynamic NRS pain score was eight and 84% of the patients had severe or moderate dynamic pain according to the BRS. On admission to hospital, the median dynamic NRS pain score was reduced to five and 45% of the patients had reduced dynamic pain according to the BRS. Among all patients, the NRS was judged to be feasible and was therefore used in 36%. Furthermore, there was an association between the decrease in pain and the increase in the number of administered medications, as well as the duration of prehospital care.

Conclusions: Patients with suspected hip fractures suffered substantial pain on EMS arrival. Only half experienced a reduction in pain on hospital admission and only 75% received pain- relieving medication.

Development of prehospital assessment findings associated with massive transfusion

Abigail R Wheeler, Camaren Cuenca, Andrew D Fisher, Michael D April, Stacy A Shackelford, Steven G Schauer

Transfusion 2020 Jun;60 Suppl 3:S70-S76

Background: Massive transfusion is frequently a component of the resuscitation of combat casualties. Because blood supplies may be limited, activation of a walking blood bank and mobilization of necessary resources must occur in a timely fashion. The development of a risk prediction model to guide clinicians for early transfusion in the prehospital setting was sought.

Study design and methods: This is a secondary analysis of a previously described data set from the Department of Defense Trauma Registry from January 2007 to August 2016 focusing on casualties undergoing massive transfusion. Serious injury was defined based on an Abbreviated Injury Scale score of 3 or greater by body region. The authors constructed multiple imputations of the model for risk prediction development. Efforts were made to internally validate the model.

Results: Within the data set, there were 15540 patients, of which 1238 (7.9%) underwent massive transfusion. In the body region injury scale model, explosive injuries (odds ratio [OR], 3.78), serious extremity injuries (OR, 6.59), and tachycardia >120/min (OR, 5.61) were most strongly associated with receiving a massive transfusion. In the simplified model, major amputations (OR, 17.02), tourniquet application (OR, 6.66), and tachycardia >120 beats/min (OR, 8.72) were associated with massive transfusion. Both models had area under the curve receiver operating characteristic values of greater than 0.9 for the model and bootstrap forest analysis.

Conclusion: In the body region injury scale model, explosive mechanisms, serious extremity injuries, and tachycardia were most strongly associated with massive transfusion. In the simplified model, major amputations, tourniquet application, and tachycardia were most strongly associated.

Prehospital Detection of Life-Threatening Intracranial Pathology: An Unmet Need for Severe TBI in Austere, Rural, and Remote Areas

Mark D Whiting, Bradley A Dengler, Carissa L Rodriguez, David Blodgett, Adam B Cohen, Adolph J Januszkiewicz, Todd E Rasmussen, David L Brody 

Front Neurol. 2020 Oct 30;11:599268. doi: 10.3389/fneur.2020.599268. eCollection 2020 

Abstract 

Severe traumatic brain injury (TBI) is a leading cause of death and disability worldwide, especially in low- and middle-income countries, and in austere, rural, and remote settings. The purpose of this Perspective is to challenge the notion that accurate and actionable diagnosis of the most severe brain injuries should be limited to physicians and other highly-trained specialists located at hospitals. Further, we aim to demonstrate that the great opportunity to improve severe TBI care is in the prehospital setting. Here, we discuss potential applications of prehospital diagnostics, including ultrasound and near-infrared spectroscopy (NIRS) for detection of life-threatening subdural and epidural hemorrhage, as well as monitoring of cerebral hemodynamics following severe TBI. Ultrasound-based methods for assessment of cerebrovascular hemodynamics, vasospasm, and intracranial pressure have substantial promise, but have been mainly used in hospital settings; substantial development will be required for prehospital optimization. Compared to ultrasound, NIRS is better suited to assess certain aspects of intracranial pathology and has a smaller form factor. Thus, NIRS is potentially closer to becoming a reliable method for non-invasive intracranial assessment and cerebral monitoring in the prehospital setting. While one current continuous wave NIRS-based device has been FDA-approved for detection of subdural and epidural hemorrhage, NIRS methods using frequency domain technology have greater potential to improve diagnosis and monitoring in the prehospital setting. In addition to better technology, advances in large animal models, provider training, and implementation science represent opportunities to accelerate progress in prehospital care for severe TBI in austere, rural, and remote areas.

War surgery in Afghanistan: a model for mass causalities in terror attacks?

F Wichlas, V Hofmann, G Strada, C Deininger 

Int Orthop. 2020 Dec;44(12):2521-2527 

Purpose: The aim of the study was to identify solution strategies from a non-governmental (NGO) hospital in a war region for violence-related injuries and to show how high-income countries (HIC) might benefit from this expertise. 

Methods: NGO trauma hospital in Lashkar Gah, Afghanistan. Four hundred eighty-four war victims admitted in a three month period (February 2016-May 2016) were included. Patients´ characteristics were analyzed. 

Results: The mean age was 23.5 years. Four hundred thirty-four (89.9%) were male, and 50 (10.1%) were female. The most common cause of injury was bullet injuries, shell injuries, and mine injuries. The most common injured body region was the lower extremity, upper extremity, and the chest or the face. Apart from surgical wound care and debridements, which were performed on every wound in the operation theatre, laparotomy was the most common surgical procedure, followed by installation of a chest drainage and amputation. 

Conclusion: The surgical expertise and clear pathways outweigh modern infrastructure. In case of a mass casualty incident, fast decision-making with basic diagnostic means in order to take rapid measurements for life-saving therapies could make the difference.

Mil Med. 2020 Dec 30;185(11-12):484-486

Radial Pulse Quality as a Diagnostic Test in Tactical Combat Casualty Care 

John M Wightman 

No abstract available

Valproic acid improves survival and decreases resuscitation requirements in a swine model of prolonged damage control resuscitation

Aaron M Williams, Umar F Bhatti, Ben E Biesterveld, Nathan J Graham, Kiril Chtraklin, Jing Zhou, Isabel S Dennahy, Ranganath G Kathawate, Claire A Vercruysse, Rachel M Russo, Yongqing Li, Hasan B Alam 

J Trauma Acute Care Surg. 2019 Aug;87(2):393-401 

Background: Although damage control resuscitation (DCR) is routinely performed for short durations, prolonged DCR may be required in military conflicts as a component of prolonged field care. Valproic acid (VPA) has been shown to have beneficial properties in lethal hemorrhage/trauma models. We sought to investigate whether the addition of a single dose of VPA to a 72-hour prolonged DCR protocol would improve clinical outcomes. 

Methods: Fifteen Yorkshire swine (40-45 kg) were subjected to lethal (50% estimated total blood volume) hemorrhagic shock (HS) and randomized to three groups: (1) HS, (2) HS-DCR, (3) HS-DCR-VPA (150 mg/kg over 3 hours) (n = 5/cohort). In groups assigned to receive DCR, Tactical Combat Casualty Care guidelines were applied (1 hour into the shock period), targeting a systolic blood pressure of 80 mm Hg. At 72 hours, surviving animals were given transfusion of packed red blood cells, simulating evacuation to higher echelons of care. Survival rates, physiologic parameters, resuscitative fluid requirements, and laboratory profiles were used to compare the clinical outcomes. 

Results: This model was 100% lethal in the untreated animals. DCR improved survival to 20%, although this was not statistically significant. The addition of VPA to DCR significantly improved survival to 80% (p < 0.01). The VPA-treated animals also had significantly (p < 0.05) higher systolic blood pressures, lower fluid resuscitation requirements, higher hemoglobin levels, and lower creatinine and potassium levels. 

Conclusion: VPA administration improves survival, decreases resuscitation requirements, and improves hemodynamic and laboratory parameters when added to prolonged DCR in a lethal hemorrhage model.

Cost-effectiveness analysis of tranexamic acid for the treatment of traumatic brain injury, based on the results of the CRASH-3 randomised trial: a decision modelling approach

Jack Williams, Ian Roberts, Haleema Shakur-Still, Fiona E Lecky, Rizwana Chaudhri, Alec Miners 

BMJ Glob Health. 2020 Sep;5(9):e002716. doi: 10.1136/bmjgh-2020-002716 

Introduction: An estimated 69 million traumatic brain injuries (TBI) occur each year worldwide, with most in low-income and middle-income countries. The CRASH-3 randomised trial found that intravenous administration of tranexamic acid within 3 hours of injury reduces head injury deaths in patients sustaining a mild or moderate TBI. We examined the cost-effectiveness of tranexamic acid treatment for TBI. 

Methods: A Markov decision model was developed to assess the cost-effectiveness of treatment with and without tranexamic acid, in addition to current practice. We modelled the decision in the UK and Pakistan from a health service perspective, over a lifetime time horizon. We used data from the CRASH-3 trial for the risk of death during the trial period (28 days) and patient quality of life, and data from the literature to estimate costs and long-term outcomes post-TBI. We present outcomes as quality-adjusted life years (QALYs) and 2018 costs in pounds for the UK, and US dollars for Pakistan. Incremental cost-effectiveness ratios (ICER) per QALY gained were estimated, and compared with country specific cost-effective thresholds. Deterministic and probabilistic sensitivity analyses were also performed. 

Results: Tranexamic acid was highly cost-effective for patients with mild TBI and intracranial bleeding or patients with moderate TBI, at £4288 per QALY in the UK, and US$24 per QALY in Pakistan. Tranexamic acid was 99% and 98% cost-effective at the cost-effectiveness thresholds for the UK and Pakistan, respectively, and remained cost-effective across all deterministic sensitivity analyses. Tranexamic acid was even more cost-effective with earlier treatment administration. The cost-effectiveness for those with severe TBI was uncertain. 

Conclusion: Early administration of tranexamic acid is highly cost-effective for patients with mild or moderate TBI in the UK and Pakistan, relative to the cost-effectiveness thresholds used. The estimated ICERs suggest treatment is likely to be cost-effective across all income settings globally.

Safety profile and impact of low-titer group O whole blood for emergency use in trauma

James Williams, Nicholas Merutka, David Meyer, Yu Bai, Samuel Prater, Rodolfo Cabrera, John B Holcomb, Charles E Wade, Joseph D Love, Bryan A Cotton

J Trauma Acute Care Surg 2020 Jan;88(1):87-93 

Purpose: Following US military implementation of a cold-stored whole blood program, several US trauma centers have begun incorporating uncrossmatched, group O cold-stored whole blood into civilian trauma resuscitation. We set out to evaluate the safety profile, transfusion reactions events, and impact of low-titer group O whole blood (LTO-WB) at our center.

Methods: In November 2017, we added LTO-WB to each of our helicopters and to our emergency department (ED) refrigerator, alongside that of existing red blood cells and plasma. We collected information on all patients with trauma receiving prehospital or ED transfusion of uncrossed, emergency release blood products between November 2017 and June 2018.

Patients were divided into those receiving any LTO-WB and those receiving only red blood cell and or plasma (COMP). Serial hemolysis panels were obtained at 3 hours, 24 hours, and 48 hours. All data were run using STATA 12.1. Statistical significance was set at p < 0.05.

Results: One hundred ninety-eight patients received LTO-WB and 152 patients received COMP. There were no differences in age, sex, or mechanism. The LTO-WB patients had higher chest Abbreviated Injury Scale scores (median, 3 vs. 2; p = 0.027), as well as worse arrival base excess (median, -7 vs. -5; p = 0.014) and lactate (5.1 vs. 3.5; p < 0.001). The LTO-WB patients received less post-ED blood products than the COMP patients (median, 0 vs. 3; p = 0.001). There was no difference in survival (LTO-WB, 73%; COMP, 74%; p = 0.805). There were only two suspected transfusion reactions, both in the COMP group (p = 0.061). There was no difference in hemolysis panel values. Controlling for age, severity of injury, and prehospital physiology, LTO-WB was associated with a 53% reduction in post-ED blood product transfusion (odds ratio, 0.47; 0.23-0.94 95% CI; p = 0.033) and two-fold increase in likelihood of survival (odds ratio, 2.19; 1.01-4.76 95% CI; p = 0.047).

Conclusion: Low-titer group O whole blood has similar evidence of laboratory hemolysis, similar transfusion reaction rates, and is associated with a reduction in post-ED transfusions and increase likelihood of survival.

Level of evidence: Therapeutic, Level II.

A prospective observational study of acute traumatic coagulopathy in traumatic bleeding from the battlefield

Tom Woolley, Robert Gwyther, Kiran Parmar, Emrys Kirkman, Sarah Watts, Mark Midwinter, Juandir Dalle Lucca, Beverley J Hunt

Transfusion 2020 Jun;60 Suppl 3:S52-S61 

Background: Acute trauma coagulopathy (ATC) after military trauma has not been comprehensively studied. ATC is defined as a prolonged prothrombin time ratio (PTr) or reduced clot amplitude (A5) in viscoelastic testing. Compared to civilian trauma, military trauma has more injuries from explosions and gunshot wounds (GSWs), potentially leading to a different pathophysiology for traumatic coagulopathy. This study aimed to characterize military ATC on admission to a military hospital in Afghanistan and to explore any differences due to the mechanism of injury.

Methods: Severely injured military casualties were enrolled in the study. Blood samples were taken on admission and after routine testing, waste plasma was prepared, frozen, and transported to the United Kingdom for in-depth hemostatic analysis.

Results: Seventy-seven percent of casualties had ATC defined by a PTr greater than 1.2 and 19% when defined by rotational thromboelastometry (ROTEM) A5 less than 36 mm.

Coagulation factor depletion correlated with degree of shock, particularly factor V (p < 0.01), factor X (p < 0.01), and fibrinogen levels (p < 0.01). Thrombin generation was well preserved. Fibrinolytic biomarkers were raised correlating with the degree of shock (p < 0.01), and 8% of casualties had hyperfibrinolysis on ROTEM analysis. Plasmin-antiplasmin complexes (p < 0.01) and d-dimer levels (p = 0.01) were higher and clot firmness lower (p = 0.02) in those injured by explosion compared to GSW's.

Conclusions: ATC was present and correlated with shock, similar to civilian trauma. Thrombin generation remained adequate. Fibrinogen and factor V levels were disproportionately low but still sufficient to allow clot formation. Fibrinolysis is a key feature, probably due to a tissue plasminogen activator surge at the time of injury. Blast injuries are associated with a greater activation of fibrinolysis than GSWs.

Prototype of a Military Medic Smartphone Medical Graphical User Interface for Use by Medics in Deployed Environments

Kenneth H Wong, Shijir Bayarsaikhan, Betty A Levine, Seong K Mun

Mil Med 2020 Jan 7;185(Suppl 1):536-543 

Abstract

Introduction: Prompt and effective combat casualty care is essential for decreasing morbidity and mortality during military operations. Similarly, accurate documentation of injuries and treatments enables quality care, both in the immediate postinjury phase and the longer-term recovery. This article describes efforts to prototype a Military Medic Smartphone (MMS) for use by combat medics and other health care providers who work in austere environments.

Materials and methods: The MMS design builds on previous electronic health record systems and is based on observations of medic workflows. It provides several functions including a compact yet efficient physiologic monitor, a communications device for telemedicine, a portable reference library, and a recorder of casualty care data from the point of injury rearward to advanced echelons of care. Apps and devices communicate using an open architecture to support different sensors and future expansions.

Results: The prototype MMS was field tested during live exercises to generate qualitative feedback from potential users, which provided significant guidance for future enhancements.

Conclusions: The widespread deployment of this type of device will enable more effective health care, limit the impact of battlefield injuries, and save lives.

Fentanyl impairs but ketamine preserves the microcirculatory response to hemorrhage

Lusha Xiang, Alfredo S Calderon, Harold G Klemcke, Laura L Scott, Carmen Hinojosa- Laborde, Kathy L Ryan

J Trauma Acute Care Surg 2020 Feb 10; Online ahead of print. 

Abstract

Background: Peripheral vasoconstriction is the most critical compensating mechanism following hemorrhage to maintain blood pressure. On the battlefield, ketamine rather than opioids is recommended for pain management in case of hemorrhage but effects of analgesics on compensatory vasoconstriction are not defined. We hypothesized that fentanyl impairs but ketamine preserves the peripheral vasoconstriction and blood pressure compensation following hemorrhage.

Method: Sprague Dawley rats (11-13wk) were randomly assigned to control (saline vehicle), fentanyl, or ketamine-treated groups with or without hemorrhage (n = 8 or 9 for each group). Rats were anesthetized with Inactin (ip. 10mg/100g) and the spinotrapezius muscles were prepared for microcirculatory observation. Arteriolar arcades were observed with a Nikon microscope and vessel images and arteriolar diameters (AD) were recorded by using Nikon NIS Elements Imaging Software. After baseline perimeters were recorded, the arterioles were topically challenged with saline, fentanyl, or ketamine at concentrations relevant to intravenous analgesic doses to determine direct vasoactive effects. After arteriolar diameters returned to baseline, 30% of total blood volume was removed in 25 min. Ten minutes after hemorrhage, rats were intravenously injected with an analgesic dose of fentanyl (0.6μg/100g), ketamine (0.3mg/100g), or a comparable volume of saline. For each drug or vehicle administration, the total volume injected was 0.1 ml/100g. Blood pressure, heart rate, and arteriolar responses were monitored for 40 minutes.

Results: Topical fentanyl induced vasodilation (17 ± 2%) but ketamine caused vasoconstriction (-15 ± 4%, p < 0.01). Following hemorrhage, intravenous ketamine did not affect blood pressure or respiratory rate, while fentanyl induced a slight and transient (<5 min, p = 0.03 vs saline group) decrease in blood pressure, with a profound and prolonged suppression in respiratory rate (>10 minutes, with a peak inhibition of 57 ± 8% of baseline, p < 0.01). The compensatory vasoconstriction observed after hemorrhage was not affected by ketamine treatment. However, after fentanyl injection, although changes in blood pressure were transiently present, arteriolar constriction to hemorrhage was absent and replaced with a sustained vasodilation (78 ± 25% to 36 ± 22% of baseline during the 40 minutes after injection, p < 0.01).

Conclusion: Ketamine affects neither systemic nor microcirculatory compensatory responses to hemorrhage, providing preclinical evidence that ketamine may help attenuate adverse physiological consequences associated with opioids following traumatic hemorrhage.

Microcirculatory responses are more sensitive than systemic response for evaluation of hemodynamic stability during procedures associated with pain management.

Sufentanil blunts the myocardial stress induced by tracheal intubation in older adult patients with coronary heart disease better than equipotent fentanyl

 

Yanchao Yang, Xiufei Teng, Junchao Zhu 

Ann Palliat Med. 2020 Nov;9(6):3909-3914 

Background: To evaluate the role of sufentanil and fentanyl in the prevention of cardiovascular responses to endotracheal intubation in elderly patients with coronary heart disease (CHD). 

Methods: Fifty CHD patients scheduled for coronary artery bypass grafting (CABG) (off-pump) under general anesthesia were randomly divided into two groups to receive either 0.4 µg/kg of sufentanil (n=35) or 4 µg/kg of fentanyl (n=36) in a double-blind manner. Under local anesthesia, an invasive arterial catheter is used to monitor systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial blood pressure (MAP). Laryngoscopy and tracheal intubation were successfully performed within 30 seconds. MAP and heart rate (HR) were recorded before anesthesia induction, immediately before intubation, at intubation, and 1, 3, 5 min after tracheal intubation. Rate pressure product (RPP) is calculated by SBP multiple HR. 

Results: Patients in the fentanyl group showed a significant increase in MAP, HR, and RPP associated with tracheal intubation. However, the cardiovascular stimulation induced by tracheal intubation was attenuated in the sufentanil group. 

Conclusions: Laryngoscope and endotracheal intubation may cause adverse increases in blood pressure (BP) and HR in elderly patients with CHD, resulting in an imbalance of myocardial oxygen consumption and supply and myocardial ischemia. Anesthesia induction with sufentanil 0.4 µg/kg is more potential than fentanyl 4 µg/kg to attenuate the cardiovascular intubation response.

Application of chain-based sponge dressing for gunshot wounds in the groin

Weijin Yang, Junchuan Song, Yuewen Zhu, Zhi Ye, Mingwei Wang, Yongchao Fang, Weihang Wu, Dongsheng Chen, Yu Wang 

Am J Emerg Med. 2021 Jan;39:24-27 

Background: With the application of limb tourniquet, junctional hemorrhage has outstripped extremity hemorrhage as the leading cause of death during recent conflicts in Afghanistan and Iraq. We used a gunshot wound femoral artery bleeding model to verify the effect of chain-based sponge dressing (CSD). 

Methods: We used a rifle to shoot the femoral artery of female Bama miniature pigs to achieve a gunshot wound model. Pigs were immediately subjected to CSD (n = 4) or standard gauze (SG; n = 4) to achieve hemostasis. We compared outcomes between the CSD and SG groups. 

Results: There was no significant difference in baseline data between the two groups. The average hemorrhage time was 38.75 ± 9.29 s after CSD and 630.75 ± 169.46 s after SG (p < 0.05). The success rate in the CSD group was 100% (4/4), while the success rate in the SG group was 25% (1/4). The survival time of the CSD group (120 min) was significantly longer compared with the SG group (62.25 min; p < 0.05). There was no statistically significant difference in the average time for removal of the hemostatic material between the two groups. One week after the experiment, animals had a normal diet and were walking. No secondary damage was caused by CSD. 

Conclusion: We used a gun-shot wound model to verify the effectiveness of CSD in the groin area. CSD achieved hemostasis quickly in all animals, and mean arterial pressure remained at normal levels. These findings suggest that CSD may be appropriate for humans with junctional hemorrhage due to bullet wounds, although further research is needed.

Incidence of injuries and factors related to injuries in combat soldiers

Nirit Yavnai, S Bar-Sela, M Pantanowitz, S Funk, G Waddington, L Simchas, S Svorai- Litvak, N Steinberg

BMJ Mil Health 2020 Feb 20; Online ahead of print. 

Abstract

Introduction: Musculoskeletal injuries to the lower extremities are major factors contributing to drop out from military tasks. The aim of the present study was to determine the incidence of musculoskeletal injuries and the parameters that differentiate between the soldiers who incurred these injuries and those who did not along 14 weeks of an infantry commanders course.

Methods: One-hundred and sixty-eight participants were recruited from an infantry commanders course. The soldiers were tested before (pre), in the middle (middle) and at the end (last) of the course for anthropometric measurements, proprioceptive ability and dynamic postural balance (DPB), and filled out an ankle stability questionnaire (Cumberland Ankle Instability Tool (CAIT). A physiotherapist followed and recorded all musculoskeletal injuries incurred by the participants during the course.

Results: Fifty-eight participants out of the 168 (34.5%) reported some pain/injury. Time effects were found for body mass index, DPB asymmetry, DPB in posterior-medial (P-M) direction and proprioception ability. Injury effects were found for DPB asymmetry, DPB in P-M direction, CAIT and proprioception ability. An interaction was found for proprioception ability. The Cox regression showed that the variables that are mostly effecting injuries were pretesting proprioception ability, DPB asymmetry and CAIT.

Conclusions: More than one out of three participants incurred musculoskeletal injuries, with deficits in proprioception ability, DPB and ankle stability in pretesting as major factors contributing to injuries. Further studies should look at the effect of specific exercises such as proprioception, DPB and ankle stability exercises for prevention and treatment of musculoskeletal injuries among combat soldiers.

Transfusion of Uncrossmatched Group O Erythrocyte-containing Products Does Not Interfere with Most ABO Typings

Mark H Yazer, Philip C Spinella, Leilani Doyle, Richard M Kaufman, Robyn Dunn, John R Hess, Luiz Amorim Filho, Magali Fontaine, Birgit Gathof, Bryon Jackson, Michael F Murphy, Jeremiah Pasion, Jay S Raval, Kristin Rosinski, Jansen Seheult, Andrew W Shih, Jason Sperry, Julie Staves, Erin E Tuott, Alyssa Ziman, Darrell J Triulzi, Biomedical Excellence for Safer Transfusion Collaborative

Anesthesiology 2020 Mar;132(3):525-534

Background: Group O erythrocytes and/or whole blood are used for urgent transfusions in patients of unknown blood type. This study investigated the impact of transfusing increasing numbers of uncrossmatched type O products on the recipient's first in-hospital ABO type.

Methods: This was a retrospective cohort study. Results of the first ABO type obtained in adult, non-type O recipients (i.e., types A, B, AB) after receiving at least one unit of uncrossmatched type O erythrocyte-containing product(s) for any bleeding etiology were analyzed along with the number of uncrossmatched type O erythrocyte-containing products administered in the prehospital and/or in hospital setting before the first type and screen sample was drawn.

Results: There were 10 institutions that contributed a total of 695 patient records. Among patients who received up to 10 uncrossmatched type O erythrocyte-containing products, the median A antigen agglutination strength in A and AB individuals on forward typing (i.e., testing the recipient's erythrocytes for A and/or B antigens) was the maximum (4+), whereas the median B antigen agglutination strength among B and AB recipients of up to 10 units was 3 to 4+. The median agglutination strength on the reverse type (i.e., testing the recipient's plasma for corresponding anti-A and -B antibodies) was very strong, between 3 and 4+, for recipients of up to 10 units of uncrossmatched erythrocyte-containing products. Overall, the ABO type of 665 of 695 (95.7%; 95% CI, 93.9 to 97.0%) of these patients could be accurately determined on the first type and screen sample obtained after transfusion of uncrossmatched type O erythrocyte- containing products.

Conclusions: The transfusion of smaller quantities of uncrossmatched type O erythrocyte- containing products, in particular up to 10 units, does not usually interfere with determining the recipient's ABO type. The early collection of a type and screen sample is important.

Pelvic gauze packing combined with an external fixator for the treatment of unstable pelvic fractures with a huge retroperitoneal hematoma: a case report

 Haibo Yu, Haifeng Huang, Yibing Jin 

Ann Palliat Med. 2020 Nov;9(6):4371-4376 

Abstract 

Pelvic fractures with retroperitoneal hematoma are frequent injuries, and there are multiple treatment options for patients. In this case, a 35-year-old female patient suffered an unstable pelvic fracture due to a car crash, accompanied by the formation of a huge retroperitoneal hematoma. The vital signs of patient were not stable. The patient immediately underwent active anti-shock therapies such as multi-channel infusion, blood transfusion, blood volume supplementation, and blood pressure elevation. However, the vital signs of patient remained unstable, the abdominal circumference increased, hemoglobin decreased rapidly, and the plasma protamine paracoagulation (3P) test was positive. So, tracheal intubation and mechanical ventilation were performed. Experts from various departments were invited to form an emergency multidisciplinary team (MDT), and exploratory laparotomy was selected. Intraoperative exploration revealed the formation of a huge retroperitoneal hematoma, and there was no bleeding or abdominal organ rupture. So, five large gauzes were developed and packed into the extra peritoneal space to stanch bleeding. Following successful hemostasis, the pelvic external fixator was positioned. Re-surgery was performed 78 hours after surgery to remove all gauzes. At 2.5 months postoperatively, the pelvic external fixator was also removed. Ultimately, the patient achieved good surgical results. Pelvic gauze packing combined with an external fixator is a rapid and effective treatment strategy for critical and huge retroperitoneal hematomas caused by unstable pelvic fractures. To our knowledge, this has not been previously reported.

Hydroxyethyl Starch for Fluid Replacement Therapy in High-Risk Surgical Patients: Context and Caution

Fernando G Zampieri, Alexandre B Cavalcanti

JAMA 2020 Jan 21;323(3):217-218 

Hydroxyethyl starch (HES) solutions have had a turbulent history as resuscitation fluids. There was initial optimism that these products would efficiently expand the intravascular space with a prolonged intravascular half-life and therefore would be “volume sparing,” with less edema.

However, enthusiasm was tempered when HES solutions were reported to be harmful when administered to critically ill patients, including those with sepsis. Despite these concerns, HES is still used in surgery under the premise that lower doses infused under strict protocols would be safe. Futier and colleagues report the results of the FLASH multicenter randomized clinical trial, which assessed the effects of HES vs saline for fluid resuscitation in patients undergoing major abdominal surgery. The primary end point was a composite of death and occurrence of renal, respiratory, cardiovascular, infectious, or surgical complications. Several secondary and exploratory end points were also reported. The FLASH clinical trial suggests that a protocolized surgical optimization approach using HES vs saline resulted in minor physiological benefits on day 1 that vanished soon thereafter. However, important morbidity for patients, specifically acute kidney injury, may be related to HES use.

Complications of cricothyroidotomy versus tracheostomy in emergency surgical airway management: a systematic review

Fabricio Batistella Zasso, Kong Eric You-Ten, Michelle Ryu, Khrystyna Losyeva, Jaya Tanwani, Naveed Siddiqui 

BMC Anesthesiol. 2020 Aug 27;20(1):216 

Background: Airway guidelines recommend an emergency surgical airway as a potential life-saving treatment in a "Can't Intubate, Can't Oxygenate" (CICO) situation. Surgical airways can be achieved either through a cricothyroidotomy or tracheostomy. The current literature has limited data regarding complications of cricothyroidotomy and tracheostomy in an emergency situation. The objective of this systematic review is to analyze complications following cricothyroidotomy and tracheostomy in airway emergencies. 

Methods: This synthesis of literature was exempt from ethics approval. Eight databases were searched from inception to October 2018, using a comprehensive search strategy. Studies were included if they were randomized controlled trials or observational studies reporting complications following emergency surgical airway. Complications were classified as minor (evolving to spontaneous remission or not requiring intervention or not persisting chronically), major (requiring intervention or persisting chronically), early (from the start of the procedure up to 7 days) and late (beyond 7 days of the procedure). 

Results: We retrieved 2659 references from our search criteria. Following the removal of duplicates, title and abstract review, 33 articles were selected for full-text reading. Twenty-one articles were finally included in the systematic review. We found no differences in minor, major or early complications between the two techniques. However, late complications were significantly more frequent in the tracheostomy group [OR (95% CI) 0.21 (0.20-0.22), p < 0.0001]. 

Conclusions: Our results demonstrate that cricothyroidotomies performed in emergent situations resulted in fewer late complications than tracheostomies. This finding supports the recommendations from the latest Difficult Airway Society (DAS) guidelines regarding using cricothyroidotomy as the technique of choice for emergency surgical airway. However, emergency cricothyroidotomies should be converted to tracheostomies in a timely fashion as there is insufficient evidence to suggest that emergency cricothyrotomies are long term airways.

Shock index and pulse pressure as triggers for massive transfusion

Caroline S Zhu, Danielle Cobb, Rachelle B Jonas, Douglas Pokorny, Meenakshi Rani, Tracy Cotner-Pouncy, Jenny Oliver, Andrew Cap, Ramon Cestero, Susannah E Nicholson, Brian J Eastridge, Donald H Jenkins

J Trauma Acute Care Surg 2019 Jul;87(1S Suppl 1):S159-S164 

Abstract

Background: Hemorrhage is the most common cause of preventable death in trauma patients. These mortalities might be prevented with prehospital transfusion. We sought to characterize injured patients requiring massive transfusion to determine the potential impact of a prehospital whole blood transfusion program. The primary goal of this analysis was to determine a method to identify patients at risk of massive transfusion in the prehospital environment. Many of the existing predictive models require laboratory values and/or sonographic evaluation of the patient after arrival at the hospital. Development of an algorithm to predict massive transfusion protocol (MTP) activation could lead to an easy-to-use tool for prehospital personnel to determine when a patient needs blood transfusion.

Methods: Using our Level I trauma center's registry, we retrospectively identified all adult trauma patients from January 2015 to August 2017 requiring activation of the MTP. Patients who were younger than 18 years, older than 89 years, prisoners, pregnant women, and/or with nontraumatic hemorrhage were excluded from the study. We retrospectively collected data including demographics, blood utilization, variable outcome data (survival, length of stay, intensive care unit days, ventilator days), prehospital vital signs, prehospital transport times, and Injury Severity Score. The independent-samples t test and χ test were used to compare the group who died to the group who survived. p < 0.05 was considered significant. Based on age and mechanism of injury, relative risk of death was calculated. Graphs were generated using Microsoft Excel software to plot patient variables.

Results: Our study population of 102 MTP patients had an average age of 42 years and average Injury Severity Score of 29, consisted of 80% males (82/102), and was 66% blunt trauma (67/102). The all-cause mortality was 67% (68/102). The positive predictive value of death for patients with pulse pressure of less than 45 and shock index of greater than 1 was

0.78 for all patients, but was 0.79 and 0.92 for blunt injury and elderly patients, respectively.

Conclusions: Our data demonstrate a high mortality rate in trauma patients who require MTP despite short transport times, indicating the need for early intervention in the prehospital environment. Given our understanding that the most severely injured patients in hemorrhagic shock require blood resuscitation, this study demonstrates that this subset of trauma patients requiring massive transfusion can be identified in the prehospital setting. We recommend using Emergency Medical Services pulse pressure in combination with shock index to serve as a trigger for initiation of prehospital whole blood transfusion.

Level of evidence: Therapeutic/care management, level V.

Efficacy of prehospital administration of fibrinogen concentrate in trauma patients bleeding or presumed to bleed (FIinTIC): A multicentre, double-blind, placebo-controlled, randomised pilot study

Bernhard Ziegler, Mirjam Bachler, Hubert Haberfellner, Christian Niederwanger, Petra Innerhofer, Tobias Hell, Marc Kaufmann, Marc Maegele, Uriel Martinowitz, Carolin Nebl, Elgar Oswald, Herbert Schöchl, Bettina Schenk, Markus Thaler, Benjamin Treichl, Wolfgang Voelckel, Ivana Zykova, Christine Wimmer, Dietmar Fries, FIinTIC study group 

Eur J Anaesthesiol. 2021 Apr 1;38(4):348-357 

Background: Trauma-induced coagulopathy (TIC) substantially contributes to mortality in bleeding trauma patients. 

Objective: The aim of the study was to administer fibrinogen concentrate in the prehospital setting to improve blood clot stability in trauma patients bleeding or presumed to bleed. 

Design: A prospective, randomised, placebo-controlled, double-blinded, international clinical trial. 

Setting: This emergency care trial was conducted in 12 Helicopter Emergency Medical Services (HEMS) and Emergency Doctors' vehicles (NEF or NAW) and four trauma centres in Austria, Germany and Czech Republic between 2011 and 2015. 

Patients: A total of 53 evaluable trauma patients aged at least 18 years with major bleeding and in need of volume therapy were included, of whom 28 received fibrinogen concentrate and 25 received placebo. 

Interventions: Patients were allocated to receive either fibrinogen concentrate or placebo prehospital at the scene or during transportation to the study centre. 

Main outcome measures: Primary outcome was the assessment of clot stability as reflected by maximum clot firmness in the FIBTEM assay (FIBTEM MCF) before and after administration of the study drug. 

Results: Median FIBTEM MCF decreased in the placebo group between baseline (before administration of study treatment) and admission to the Emergency Department, from a median of 12.5 [IQR 10.5 to 14] mm to 11 [9.5 to 13] mm (P = 0.0226), but increased in the FC Group from 13 [11 to 15] mm to 15 [13.5 to 17] mm (P = 0.0062). The median between-group difference in the change in FIBTEM MCF was 5 [3 to 7] mm (P < 0.0001). Median fibrinogen plasma concentrations in the fibrinogen concentrate Group were kept above the recommended critical threshold of 2.0 g l-1 throughout the observation period. 

Conclusion: Early fibrinogen concentrate administration is feasible in the complex and time-sensitive environment of prehospital trauma care. It protects against early fibrinogen depletion, and promotes rapid blood clot initiation and clot stability.

"Decompression of tension pneumothorax in a trauma patient -first use of a novel decompression colorimetric capnography device in human patient"

John Zietlow, Matthew Hernandez, Andrew Bestland, Juna Musa, Michael Ferrara, Kathleen Berns, Jeff Anderson, Martin Zielinski, Johnathon Aho 

Case Reports Gen Thorac Cardiovasc Surg. 2021 Feb;69(2):391-393 

Abstract 

Tension pneumothorax is a common cause of mortality in trauma. Tension pneumothorax is the confinement of respired gases within the pleural cavity at increasing pressure resulting in hemodynamic collapse. Decompression is crucial in management. Emergency needle thoracostomy is a life-saving maneuver that allows atmospheric pressure equilibration and partial restoration of cardiac filling. Needle decompressions are usually performed under noisy, tense, and stressful circumstances, and objective assessment of success is difficult in the field. A device which is simple that objectively informs operators of successful decompression would be clinically useful. In previous work, we have demonstrated end-expiratory gas and gaseous composition of tension pneumothorax are similar due to increased carbon dioxide partial pressure relative to atmospheric gas composition. Therefore, a simple solution to objective needle decompression may be colorimetric capnography.We report a case of 58-year-old male treated by EMS following a motorcycle accident with left-sided chest pain, hypoxia, hypotension, and clinical findings of tension pneumothorax. Needle decompression with colorimetric capnography using the device indicated decompression of his tension pneumothorax, with appropriate temporizing success.

Early Antibiotic Administration Is Associated with a Reduced Infection Risk When Combined with Primary Wound Closure in Patients with Open Tibia Fractures

David A Zuelzer, Christopher B Hayes, Gavin S Hautala, Adam Akbar, Ryan R Mayer, Cale A Jacobs, Raymond D Wright, Eric S Moghadamian, Paul E Matuszewski 

Clin Orthop Relat Res. 2021 Mar 1;479(3):613-619 

Background: Early administration of antibiotics and wound coverage have been shown to decrease the deep infection risk in all patients with Type 3 open tibia fractures. However, it is unknown whether early antibiotic administration decreases infection risk in patients with Types 1, 2, and 3A open tibia fractures treated with primary wound closure. 

Questions/purposes: (1) Does decreased time to administration of the first dose of antibiotics decrease the deep infection risk in all open tibia fractures with primary wound closure? (2) What patient demographic factors are associated with an increased deep infection risk in Types 1, 2, and 3A open tibia fractures with primary wound closure? 

Methods: We identified 361 open tibia fractures over a 5-year period at a Level I regional trauma center that receives direct admissions and transfers from other hospitals which produces large variation in the timing of antibiotic administration. Patients were excluded if they were younger than 18 years, had associated plafond or plateau fractures, associated with compartment syndrome, had a delay of more than 24 hours from injury to the operating room, underwent repeat débridement procedures, had incomplete data, and were treated with negative-pressure dressings or other adjunct wound management strategies that would preclude primary closure. Primary closure was at the descretion of the treating surgeon. We included patients with a minimum follow-up of 6 weeks with assessment at 6 months and 12 months. One hundred forty-three patients with were included in the analysis. Our primary endpoint was deep infection as defined by the CDC criteria. We obtained chronological data, including the time to the first dose of antibiotics and time to surgical débridement from ambulance run sheets, transferring hospital records, and the electronic medical record to answer our first question. We considered demographics, American Society of Anesthesiologists classification, mechanism of injury, smoking status, presence of diabetes, and Injury Severity Score in our analysis of other factors. These were compared using one-way ANOVA, chi-square, or Fisher's exact tests. Binary regression was used to to ascertain whether any factors were associated with postoperative infection. Receiver operator characteristic curves were used to identify threshold values. 

Results: Increased time to first administration of antibiotics was associated with an increased infection risk in patients who were treated with primary wound closure; the greatest inflection point on that analysis occurred at 150 minutes, when the increased infection risk was greatest (20% [8 of 41] versus 4% [3 of 86]; odds ratio 5.6 [95% CI 1.4 to 22.2]; p = 0.01). After controlling for potential confounding variables like age, diabetes and smoking status, none of the variables we evaluated were associated with an increased risk of deep infection in Type 1, 2, and 3A open tibia fractures in patients treated with primary wound closure. 

Conclusion: Our findings suggest that in open tibia fractures, which receive timely antibiotic administration, primary wound closure is associated with a decreased infection risk. We recognize that more definitive studies need to be performed to confirm these findings and confirm feasibility of early antibiotic administration, especially in the pre-hospital context.

Freeze-dried plasma stability under prehospital field conditions

Meital Zur, Elon Glassberg, Pavel Gorenbein, Elad Epstein, Arik Eisenkraft, Mudi Misgav, Eva Avramovich

Transfusion 2019 Nov;59(11):3485-3490 

Abstract

Background: This study evaluated the effect of routine, uncontrolled, Israeli field storage conditions on the stability and efficacy of Lyo-Plas N freeze-dried plasma (FDP). We evaluated clotting factors V, VIII, and XI; proteins S and C; fibrinogen; partial thromboplastin time (PTT); antithrombin III (ATIII); von Willebrand factor (VWF); and international normalized ratio (INR) in FDP stored at 4°C, 25°C, and 40°C for 6 and 12 months, as well as FDP returned from field units after uncontrolled storage for 15 months (manufacturer's shelf life).

Methods and materials: After reconstitution, clotting factor levels were compared to those of freshly supplied FDP doses.

Results: At 4°C for 12 months, factor V decreased slightly. At 25°C, average fibrinogen and factor V content were significantly lower at both periods, and INR was higher after 12 months. At 40°C, all samples were out of normal range in at least one clotting factor after 6 or 12 months.

After field storage for 15 months, fibrinogen, factors V and XI, PTT, and protein S were significantly decreased, and INR increased. However, these levels were still within laboratory norms. Statistically significant difference in clotting factors compared to laboratory normal range was found in INR (higher) and factor V (lower).

Conclusions: Our data show minimal decreases in clotting factors in FDP after storage under field conditions, when compared to laboratory normal ranges. Along with the many advantages of FDP, this supports its use at the point of injury under battlefield conditions, despite uncontrolled storage environments. Under controlled storage conditions at 4°C, shelf life could possibly be extended, although further study is required.

Multifaceted Benefit of Whole Blood Versus Lactated Ringer's Resuscitation After Traumatic Brain Injury and Hemorrhagic Shock in Mice

Benjamin E Zusman, Patrick M Kochanek, Zachary S Bailey, Lai Yee Leung, Vincent A Vagni, David O Okonkwo, Ava M Puccio, Lori A Shutter, Keri L Janesko-Feldman, Janice S Gilsdorf, Deborah A Shear, Ruchira M Jha

Neurocrit Care. 2020 Sep 4;10.1007/s12028-020-01084-1. doi: 10.1007/s12028-020-01084-1. Online ahead of print. 

Background: Despite increasing use in hemorrhagic shock (HS), whole blood (WB) resuscitation for polytrauma with traumatic brain injury (TBI) is largely unexplored. Current TBI guidelines recommend crystalloid for prehospital resuscitation. Although WB outperforms lactated Ringer's (LR) in increasing mean arterial pressure (MAP) in TBI + HS models, effects on brain tissue oxygenation (PbtO2), and optimal MAP remain undefined.

Methods: C57BL/6 mice (n = 72) underwent controlled cortical impact followed by HS (MAP = 25-27 mmHg). Ipsilateral hippocampal PbtO2 (n = 40) was measured by microelectrode. Mice were assigned to four groups (n = 18/group) for "prehospital" resuscitation (90 min) with LR or autologous WB, and target MAPs of 60 or 70 mmHg (LR60, WB60, LR70, WB70). Additional LR (10 ml/kg) was bolused every 5 min for MAP below target.

Results: LR requirements in WB60 (7.2 ± 5.0 mL/kg) and WB70 (28.3 ± 9.6 mL/kg) were markedly lower than in LR60 (132.8 ± 5.8 mL/kg) or LR70 (152.2 ± 4.8 mL/kg; all p < 0.001). WB70 MAP (72.5 ± 2.9 mmHg) was higher than LR70 (59.8 ± 4.0 mmHg, p < 0.001). WB60 MAP (68.7 ± 4.6 mmHg) was higher than LR60 (53.5 ± 3.2 mmHg, p < 0.001). PbtO2 was higher in WB60 (43.8 ± 11.6 mmHg) vs either LR60 (25.9 ± 13.0 mmHg, p = 0.04) or LR70 (24.1 ± 8.1 mmHg, p = 0.001). PbtO2 in WB70 (40.7 ± 8.8 mmHg) was higher than in LR70 (p = 0.007). Despite higher MAP in WB70 vs WB60 (p = .002), PbtO2 was similar.

Conclusion: WB resuscitation after TBI + HS results in robust improvements in brain oxygenation while minimizing fluid volume when compared to standard LR resuscitation. WB resuscitation may allow for a lower prehospital MAP without compromising brain oxygenation when compared to LR resuscitation. Further studies evaluating the effects of these physiologic benefits on outcome after TBI with HS are warranted, to eventually inform clinical trials.